One trick to check for belt noise, with the engine idling and the belts tensioned properly (not too tight or loose), CAREFULLY apply a bar of soap to each side of the fan belt. This will usually quiet a noisy belt at least temporarily.

If it's not the belt, pour a can of water pump lube into the radiator. It will quiet a noisy bearing and prolong lifespan.

Ethanol and brass are listed as having excellent compatibility in the chemical compatibility database. Plastics are a mixed bag depending on what type of plastic. HDPE, PTFE, Nylon and PET are compatible. ABS, polycarbonate, LDPE, PVC, Tygon, Silicone, polyurethane are not.
Interestingly, ethanol is not kind to aluminum either.

In my recently acquired '55 400, the speedometer cable was broken at the trans and as it turns out it's due to the speedometer head turning very stiffly. It doesn't make noise, just takes considerable effort to turn, but does turn and operate, at least until the next cable breaks. I would think it should turn freely.

Any tips on speedometer clean and lube, which I assume requires removal?

I'm in need of a left front fender for a '55 Patrician, free from dents or rustout.

BTW, I have a spare right front fender if anyone is in need. It does have a rust hole near the bottom but is dent free.

Location is in SE Washington State -- within driving distance preferred.

My '55 Patrician is an odd combination of "features". It has full leather seats in two tone green, and headliner.

BTW, that seat leather is way thicker than anything found in vehicles today.

Meanwhile, the exterior is single tone white and the power windows and seats were deleted in favor of hand operated. Apparently somebody didn't trust all that new-fangled electric stuff.

Just to bring this to closure (hopefully), the transmission and rebuilt engine were installed and the car taken for it's first test drive. The direct drive clutch now works.

Just as a follow-up, I pulled the pump plate off the pump to discover that although the plate is '56 the pump is '55. That's an incompatible combination with the plate blocking the DC oil path.

I have no idea where that '56 plate came from but I assume it somehow got swapped when the guy rebuilt it, even though his only parts vehicle was a '55 clipper.

The transmission is now reassembled with a '55 plate and will be going back to the car with the expectation the problem will be solved.
We'll see...

Thanks for the information!

Is the 20 tooth rotor a '55 part in the '56 housing, or were early '56's also 20 tooth?
Doesn't the '56 housing inject the clutch oil in the center end of the pump vs. the bell housing channel, in effect getting it to where it needs to go down the converter shaft? But then with the unnecessary drilled annular holes and/or the 20 tooth rotor is the clutch oil bleeding off where it isn't supposed to go?
Not sure I fully understand the path but I don't understand why a '56 housing wouldn't work. I guess I need to know what combination is best.

As for end play on the center shaft, by hand I don't feel any at all. It's tight. As I've mentioned this trans was reportedly entirely rebuilt but that's when the clutch quit working, but everything else works fine. I don't know what, if any, problems it had beforehand.

I drilled out the broken off cooler fitting and removed the oil tubes. Here are some pictures of the pump and bell housing. The issue is no direct drive clutch actuation though the test port pressure is within range. The converter shaft has the holes in the annular groove.

Any problems seen with mismatched parts? I notice the converter shaft is the upgraded 40 tooth but the pump rotor is 20.

https://photos.app.goo.gl/5gtyR5dEyVafeFpk7

Interesting. So the deletion of the orifice doesn't cause any pressure issues in the transmission?