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I glued in the weatherstripping that goes around the passenger door. I did not use the Steele rubber seal that I bought a while back, but rather the softer seal that was on the car years ago when I got it. It's the same profile, but a little bit softer. Anyway, the seal on the passenger door helps with keeping out fumes which are probably from the road draught tube. I drove to work this morning, and the air in the cabin is fresher than it was before. Just goes to show, everything is there for a reason!
I now have about 1200 miles on the car this season, and will soon be doing my pre-winter oil change.

In the spirit of experimentation, I re-gapped my spark plugs (AC-R45) from the factory spec of 0.028" to 0.031". (My spark plug wire gauges are metric, so I went from 0.7mm to 0.8mm)
My car is 12volt with pertronix and their 1.5 ohm coil and no ballast resistor...In the first day of driving I cannot say I noticed any difference. Nothing seat of pants, and no difference in my manifold vacuum gauge. The change is pretty small to negligible.
In the pertronix instructions, they write that with the coil, gap can be increased +0.010" which I may try out, but am not sure. That would be the widest I would ever go, but am tending to stay at or near the stock specification.
I didn't take any pictures, but all plugs looked very clean, no traces of running rich or burning oil at all.
Just thought I would share my experience. I wonder if anybody else has experience with changing gaps on the flathead engine. Looking online at what flathead ford people say, staying at the stock spec is the way to go. I'm not trying to convert anybody that wants to run points. comments?

After driving for a while with .031" spark plug gaps, I went to .035" gap. That's the spec for the V8 engines with 12 Volt systems. I might be fooling myslef, but it seems peppier. I really can't say for sure. Changing the spark plug from .028 to .035 changes the voltage required for creating a spark from 11kV to 15kV according to the Bosch literature I have...Increasing the gap however reduces the length of time that the spark is actually sparking in the plug...
One other thing I would like to experiment with is changing my ACR45 plugs to the NGK equivalent BR6S, or BP6S. The BR6S is the same as ACR45 or Autolite A308 from the size, but seems to have a wider heat range...The BP6S is a projected tip plug which puts the electrode 0.100" deeper into the combustion chamber. Of course I will check clearances to the valves before running the projected tip plugs.
Has anybody looked into these plugs for a flathead before?
Attached is a pic showing the 2 NGK plugs.

I calculated my fuel consumption, and got a average of 12 MPG over the last 2 tanks of fuel. That was with quite a bit of city driving and traffic going to and from work. I guess that is reasonable for in-town MPGs.

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As I understand it, the .028 gap is generally for positive ground where the spark has to jump from a colder surface which takes more energy but on negative ground it has to jump from a hotter surface which is easier so a wider gap is needed. When converting from positive to negative ground, this change is often overlooked but I'm not an engineer so maybe one can explain it in better detail.

By the way, below from my 1954 Patrician is the type of plugs I generally use. They are Fire Injector 14 plugs which I believe I bought from J.C. Whitney decades ago although Bosch makes similar plugs today. Not sure if J.C. Whitney still carries these but when I added them I had to tune down the idle speed and mileage improved as a result.

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Has anyone tried the E3 plugs in a flathead engine? They are similar in construction to the one Don shows with the non adjustable multi direction spark configuration. IIRC, one poster used them in a modern engine but said he had an issue with the plating but don't remember what. As heavily as they are advertised just curious if they are hype or the improvement the mfg claims.

I would say the E3 plugs are hype and I would not use them. The plugs with multiple ground strap still have 1 spark per ignition cycle, but should last longer than a normal plug due to the erosion being spread out over 4 surfaces.
Projected tip plugs were reccomended to me by a porsche engine builder who is also a retired engine management engineer. From what I read in the bosch literature on ignition systems they have less chance of misfire compared to a normal plug. That of course is with a modern combustion chamber. All of this is probably splitting hairs that wont make much or any difference, but I find the experimenting fun.
I did also index all my spark plugs so they are facing towards the pistons and not the corner of the combustion chamber....one more thing that might give me a little edge.
I also remember reading somewhere that about the spark directon that don mentioned...
Working on spark plugs is just so easy in the packard also! They are so easy to reach compared to my other cars!

If I understand Don's comment correctly, then I'm really scratching my head at why the center electrode of a spark plug would be cooler in a positive ground car than a negative ground. Have I misunderstood him, or if not, can someone enlighten me on this - it seems to defy logic?

Don, by my understanding if the plug fires from the side electrode to the center, the coil is wired incorrectly; both positive and negative ground system fire the plug from the center electrode.

If I'm wrong about this, please someone correct me.

EDIT: Not quite apples to apples, but negative ground Pontiac flathead 6s and 8s call for plug gap of 0.025".

A coil is basically a transformer which requires a buildup and drop of current to do anything. Transformers generally require AC which builds up positive, then reverses to build up negative and so forth. On a distributor it is done with DC by turning on and off the current by way of the points in the distributor which effectively does the same thing but, as DC, has one direction only. Sorry mean NW can correct me if I'm wrong but I'm not sure that connecting a coil backwards would really make any difference as it's just a matter of opening and closing the ground and I can think of nothing inside a coil where that would matter. It's basically a coil of wire inside with a switch (the distributor) turning the power off and on but the polarity of the battery and which side is ground would determine the direction of electrical flow.

Don, I appreciate the time you've taken but remain unconvinced and look forward to comments from others.