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Thanks John, I will check him out!

Got the master cylinder in today. I bench bled it first the got it fangled into place. Not much clearance between the exhaust master cylinder and steering box. I'm either going to have build a heat shield, or use some header wrap on that collector area.

Also, is the new Napa brake switch SL-134 that comes with pre tape wrapped threads.

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To protect the master cylinder and brake switch from getting baked but the exaust collector tubes, I figure I'm going to need to create a heat shield this is something like this U shape.

I figure I can pick up attachment points for a bracket at the lower collector bolt (A) and the top collector bolts (B).

I know they make all kinds of embossed stainless and aluminum heat shield sheets that are supposed to be very good heat shield material, but I fear they would look really out of place in something I am attempting to keep "period" looking. So perhaps a 18ga or 16ga piece of bent steel would work. Similar to the post war fuel pump heat shields.

The shield wouldn't wrap all the way around the collectors, as I want it open on the front (radiator) and back (firewall) sides or airflow.

Just enough to block some of the radiant heat from that exhaust, to keep from roasting the steering box and master cylinder.

Any opinions?

I was looking at header wrap, but the consensus is that it causes headers to rust out pretty quickly, and also, it doesn't look that period.

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I am always good for an opinion!
I think 18 Ga would be sufficient. For instance if you put the tray in the toaster oven and try and toast bread, the side on the tray does not toast. That is what you are looking for, a shield to reflect the heat. I like your idea of an arced form connecting at the A and B point, to separate the sealing nuts from the shield nuts is there enough stud so you can leave the nuts as they are on the manifold and run the shield onto them and use another nut on the stud to fasten the shield? If not, can you swap longer studs?
I would also suggest having the tail of the arced shield go well below the bottom of the steering gear, this would encourage cooler air to chimney up the shield and help keep it cool enough that it will not radiate too much heat through to the master/steering box area.
The shield will rust quickly if you use cold rolled steel, the heat alone stops most paints from working. You could use powder coated porcelain, but that is a bit expensive. I suggest a brushed stainless, it does not stand out as too shiny so looks a bit more period. I used some on my cars and got it from Peavy Mart, they are just a tractor/farm supply company.
Bob J.

IMO, you are on the right track. As long as there is a clear space between the shield and master so the master can get some air flow from the fan or road motion a metal shield to deflect some of the concentrated heat should go a long ways in avoiding potential issues.

Others have poo'd the idea but I am still convinced one of the reasons so many V8s seem to have BTV issues when compared to the same unit on inline 8s is that the V8 unit is very close to an exhaust manifold whereas on the inline 8s the heat source is far away on the other side of the engine.

When I did my brake playing around the master ended up too close to an exhaust pipe for my comfort level so I made a heat shield and took advantage of the round shape at the end of the master for the mounting. Made a clamping arrangement using a split collar which uses screws to compress the collar halves to hold the shield on. If you can use existing bolts and mount yours with a bit of air space between the shield and master I would think it would help a great deal.

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Howard, did you use a sheet of aluminum?

In other news.... The parts courtesy of Gary Kulp arrived! Thanks Gary, very much appreciated!

These are the inner fenders and the convertible top irons.

The critical missing top parts are the front casting pieces which attach the irons to the header bow. So any leads on these hard to fine parts is appreciated.

Also of course then wooden bows and oval steel bow will have to get made.

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It is aluminum and was just a piece of 1/8" sheet left over from another project. Probably started around 5x7" before cutting to that shape.

One of the guys on the Jag forum was nice enough to send me this picture. I guess it's from a late 60's / early 70's engine. Same XK motor, they just used different valve covers in those years. But this shield is very similar to what I was thinking. So I think I'm on the right track.

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On those inner fenders, a couple of questions:

1) Can they be installed with the fenders already in place, or do I need to dismount the fender and attach them first?

2) Along the bottom edge, there are a series of small holes. Are those for the "rubber skirt" as mentioned in Dar Kuehl's book?

3) Does anyone have a picture of what that rubber skirting looks like so I can recreate it? Trying to get an idea of length, shape and extent.