I have got a question that I'm hoping someone might be able to answer. I have a 61 W200 that I bought a few years back from the original owners, it had been sitting 25 yrs. The motor is tired and I wanna rebuild it but right now I got other projects that are getting in the way and idk when ill make time for it but I still would like to enjoy and drive the truck for now. So I seen an add for a 65 poly motor and it looks decent and not bad on price BUT! Here is my issue my 61 has a long crankshaft which has nuts and bolts holding the flywheel on and the later poly is a typical threaded crank and is a inch shorter. I measured the bellhousings and there is no difference in depth both are 8 1/4". Is there a difference on transmission input shafts on np420s and also compared to np435 too? Will the motors swap across or other does it mean transmission needs to be changed to?
thanks, Jim