[TomO]

The concerns with the full floating rod bearings are:
The over-sized bearings are hard to find.
Machine shops do not always understand that the rods must be bored to resize them for correct clearance. You cannot just grind the cap to reduce clearance.
I would also balance the engine after resizing the rods.

8BA rods with the fixed bearing must be used with a crank that has an oil hole for each rod. The bearings are easier to find. There are still some NOS cranks available. The bearings are much easier to find. The cost is probably very close to reconditioning the 29A rods and sourcing the correct floating bearings. Henry is going to need at least 2 new rods.

Also Henry needs to know that you cannot continue to drive a car with loud noises coming from the engine or drive train. If he doesn't know how to determine what is causing the noise, he should take it to a mechanic. Even mechanics that only work on modern cars, can isolate the noise in our old cars.