I lowered my '50 3600 using a 3100 front axle. To do the front properly, it is a little bit involved- the front axle comes completely apart, then Sid will stretch the axle. Smallest drop is 3 inches. You must ship axle to/from Oklahoma and your steering arms get modified as well. He did a great job on mine. There is a waiting list and you pay in advance for your spot in line- so call early if you are serious about doing it.
By the time you are done though, you could probably have installed a more modern A-arm front suspension clip with drop spindles and have better brakes as well, for just a little more money. I'd seriously think about how long you want to keep your truck and what your long term plans are for it. If you are considering going with a V8 at any time in the future, I would say go with a different front suspension. No doubt you will hear many different opinions regarding this. Good luck!
