I believe the factory wheels are 5.5 x 15. These are pretty easy to find if you are considering going without the wires. If you're set on the wires, check the skirt clearance - the back tires on these cars are a tight fit, much more so than on Clippers.

Laminated cuts more easily than tempered, I'm told.

In my opinion, fully rolled up you can't tell. But the edges look different because you can see the lamination. I believe pre-war "safety glass" was laminated, not tempered.

I suppose one could be concerned about the glass-maker's mark vs original supplier (PPG, LOF, etc) also. I think Packard used PPG just before WWII, but I'm not certain.

Don't most judging criteria specifically allow glass replacement as a safety item?

I trust you understand the tempered vs. laminated, yes? You seem concerned with detailed authenticity, and you can see the difference.

be careful with the PB blaster route - it will soften them but you might have damage to the painted surface held in contact with the bumpers. How thick are they - I have some leftover stock I made 41 door check cushions from, you can have some if it looks like it will work.

The museum's a good idea - where else can you go to Packard Dealer and ask for the Parts Department? I found it easy enough to look if you call and have a guide.

The new glass will look, well, new. The butyrate layer will be clear. Bring the old or measure to get the same thickness (laminated glass comes in various thicknesses).

the yellow convertible is a 42 8 cylinder but if I squint I think I see Junior running board trim (front edge only) and Senior bumpers (triangular ends). Very pretty

if you are having trouble finding a drum (these were high production years) I may be able to point you to as parts car

I wish to offend no Packard owners, but I think Nance modernized the styling, but in a way which resulted in much less distinctive looks. The bathtubs resembled the fuselage body efforts of the time from Hudson, Lincoln and Mercury, but with a very different front end that could only be Packard. The High Pockets cars 51-54 resembled Pontiacs and others in overall shape, and the transition to full width grills made the ox yoke shape pretty subtle. I think Packard became less visually distinctive. The 53 Caribbean pointed how to step away from the crowd more.