Sniper

Dorman shows the specs https://www.dormanproducts.com/p-11981-614-001.aspx

No, it is not a good compromise. It is what is called the correct part per the factory parts manual, see the listing in my last post.

Not true on my 51 Plymouth, he has a 51 Desoto. I want to say mine used a 7lb cap but I am not 100% sure on that. Looks like a 4lbs, 4th column is a Desoto 6, first column is Plymouth and it is a 7

I haven't run the one I linked, so I have no experience with it. Not sure if anyone here has, maybe someone can help?

Other than the radio, there is nothing in the vehicle that is hard to convert to 12v operation. Some items do not care, switches, some do care, light bulbs. If you have electric wipers and a heater then you get into issues. The wipers will work at warp speed. I used a current limiting circuit I built to slow that down, not 100% satisfied with that option though. For the heater blower, here is what I did. http://www.yourolddad.com/blower-motor For the gauges, the only one that might be affected is the fuel gauge, if your sender had two terminals it won't be, if it is a single one like my 51 it will be. A "Runtz Resistor" on the fuel gauge + terminal fixes that. The rest of the gauges, except the ammeter, are mechanical, change the bulbs and done. The ammeter will need the two wires on the terminals swapped, otherwise it will read discharge when it's charging and charging when it is actually discharging (assuming 122 negative ground). Finally, the battery will need replaced. The only mandatory items initially are the bulbs, battery and alternator. The rest can be done at your leisure.

I am running the 6v starter on my 12v converted 51. Spins faster but works just fine Or if you need one https://snap-usa.com/products/1950-1955-dodge-plymouth-mini-12-volt-starter-replaces-mch6101

A point to mention, Chrysler quit using hardened exhaust seats on engines somewhere between the flathead era and the end of leaded gas. At least on pass cars, no idea about HD truck or industrial uses.

Hate to be a downer, but did you check tire clearances?

Sorry, I was out all week in Houston. I just got back but it looks like you figured it out.

Except there is an anti-walk add on that was designed in the days of bias plies. https://www.oldmoparts.com/parts/e_wheels/chrome-valve-stem-cover/

No worky

Lots of people think this. Lots of people don't understand thermodynamics. Group A is always part of Group B. https://www.enginebasics.com/Engine Basics Root Folder/Engine Cooling.html

I have a meat thermometer I bought just for this.

This also works well for a weak heater core.

The small hole is the bypass, do not enlarge it. No thermostat, RTV, etc tells me someone had a cooling issue before you. Have the radiator flow tested, you can use the FSM method if need be. Bet it's plugged up. My 51 can idle all day long in 100+ degree heat and not have an issue. Even before the electric fan conversion.