Working on a partial 3514846 727. Listed as 383-4. It was missing pump and clutch assemblies, but planetary back all there.

The questions I have are:

The front planetary is a 4 gear, the rear is 3 gear. Is this normal, or modified at some point? Would the 383-4 trans have this?
The front servo looks like the 70 style and according to the manual the 383-4 should have the cushion style piston assembly. Also this only had the inner spring, no out spring, which the 71 SM states is 440-6 and hemi type? Was this a typical addition?

The other question I have is about shift kits. I have read through the Transgo and B&M transpak instructions. Read many post on the various forum, does some one have a document that spells out what each mod of the instruction specifically does?

The instructions really do not tell you why you are doing what your doing. Some steps can be figured out, but other not.

Example, when you drill the wall channel out with the plate, what is that doing? What does it effect? Same for some of the plate hole drilling.

Thanks,