I bought a new GM sbc from Jegs 6 or 7 years ago that was terrific. I think the key to a crate motor is to buy a new one and not a reman. Of coarse that same motor is more than twice the price now.

had one in a 1980 f150 with a 300 ci. real piece of crap. junkyard ones were expensive because of their demand, seemed to eat bearings and clusters. I'd be looking for a 5 speed.

If a magician reveals how the magic trick is accomplished, it's no longer magic.

first thing I'd do is rotate the drive shaft 180* on the rear yoke. If you want to check the DS balance you can put a hose clamp around the drive shaft and rotate it 45* at a time and see if it changes things. try it at the rear joint and if no joy, try the front joint.  As Scott said, you're spining the shaft faster and harmonics are a bitch.

yeah, I got some of that.

the 59 fords came with the transporter. I played with the cars but never the transporter because you couldn't separate it from the cab. The colored glass insulators are telephone and telegraph, some going back to the late 1800s. The solid ones are porcelain and used for electrical power.

I like motorcraft TA-31 im a Big believer after i sealed a pinhole in the radiator with water still in it
Color werry close to Aluminium easy to take apart. Even get british motorcycles to stop leaking
Sealed a crack in a board on the boat

Yeah, but the real test would it stop an oil leak on a Harley?