It merely seems that your choke needs to wound up a notch or two tighter. The black plastic disc on the side of the carb needs to be turned slightly in the direction of closing the choke. You will see that it is marked with a series of notches. I'd try moving it one notch tighter. I'm several thousand miles from a Packard just the moment, but believe it would be ccw.

JP as you surmise the number of turns is just a number. The idle settings have a small effect just off-idle, but beyond that nothing as the main jets take over.

In general, healthy engines with good spark and compression will idle quite OK even if the mixture is far from the ideal. As they get more worn it is often harder to find the sweet spot.

Similarly, engines with good compression are not usually too fussy to start. They will crank up even if the battery is low or the choke is dodgy. In contrast, with worn rings you have to follow the recipe just right and hope all contributing factors are ideal. Many older cars had 12 volts put in when they really needed rings.

I use the method preferred by all the other old farmers like myself: You turn the screws to obtain the best, smoothest idle, and that by ear.

With the car fully warmed up, I do one side at a time: turn out 1/4 turn. Listen. Better? Turn out another 1/4 turn. Repeat til it starts to sound worse. Turn back in til the best idle is achieved. Reset the idle speed if it is now racing. Now do the other needle the same way. Reset the idle speed if necessary. To be sure, repeat the whole procedure for both needles and reset the speed one last time. The whole thing takes 3 minutes.

If you have that thing back out of the car, bolt it face to face with your old pressure plate. That will help you find if there is one errant hole and you can drill just that one using the old cover as a guide.

If your pilot bearing is not seized, then just take a dab of grease on your pinky, put it through the center hole and try to work it in. Or, you can carefully pry the cover off the bearing with a wee screwdriver, service it and put the cover back on. Use only a very small amount of grease on it, and just a light film on the trans shaft before you slide it back in. Don't want anything flinging out on that new clutch.

Didn't realize the corn dogs were that good.

Gosh guy, I must have five of them in the basement and no one has ever asked for one. Have sold the occasional motor.

They can often be un-jammed by lightly grabbing the flexible coupling between the motor and gearbox with some thin pliers and turning. Or take the motor off and do it.

The forward and back units just have an acme screw, but the up/down units have recirculating ball. Both respond quite well to a little cleaning and lubing of the screw units and the angle drives, and the motor bearings. I don't notice any great tendency for them to jam except when they need servicing. Remember these things are at least 600% outside of their design service life by now.

Just for the record,if you have the drums off, you can just borrow a dial indicator with a magnetic base and stick it to the axle shaft. Bump the axles from side to side as Owen mentioned to make sure the bearings are seated before mounting the indicator. Put the indicator tip against the backing plate, and pull the axle in and out with your hand to get the reading.

As the axle ends and the center thrust block in the dif wear with time, you will almost always need less shims rather than more. Excess endplay is a sure killer of axle bearings--when there is too much play the weight of the car ends up being concentrated on one roller of the bearing at a time rather than spread over several. I try to always set them to the low end of the tolerance.

54s still have the eccentric adjustment at the anchor pin on each of the backing plates to center up the shoes in the drums. Always a good idea to readjust them when fitting new shoes to give the best contact. With them adjusted, and a bit of wearing in, you probably won't have to have the shoes arced.

There is a long and tedious procedure in the shop manual for doing this which over the last 20 years I have boiled down to this:

Loosen the locknut (15/16) and turn the eccentric (7/16)to its neutral position. You will see that the eccentric's shank is cut at a slight angle. The high point should be toward the rear of the car. Tighten the normal adjuster til the drum is dragging heavily. Now move the eccentric back and forth a bit to obtain the least drag. You might have to tighten the adjuster a bit more and repeat the process to find the point of least drag. Tighten the locknut and then adjust the brakes normally. This will give the best possible contact pattern.

Important: when doing the rear brakes, disconnect the e-brake cables at the equalizer before beginning. Only connect and adjust the cables after the individual wheels are adjusted. If the cables are pulled you will not get a correct adjustment.

Good chance that your bolts are bottoming because the face of the cover has been caved in from past overtightening. Its possible to reach through the back of the cover with a 5/16 pin punch or old bolt and tap the front surface back out.

I'd be happy to send you one (Rochester) for $55 on your doorstep. Please PM me if interested.