Help identifying 904 low gear set components

So im looking to swap a low gear set into my 71' 904 transmission, and I know I should be able to get the parts I need from my local transmission parts house. However, I am not sure which variety of the parts I need. I know anything later than 82' with a 904 variant or A-500 should have what I need. I also know (or believe I know) that the parts necessary are the sun shell, the sun gear, the front planet(I already have a 4 pinion steel front planet that I was hoping could work), and the ring gear (with hub?). Problem is, in the parts catalogs there are so many options im not sure which to go with.

For example, for the same model years, sun gears are offerred in overdrive straight, 22 degree angled and 15 degree angled teeth...or I can get a sun gear and shell together, but both are for the same model years and described as large planet, 5" OD ring gear, with either 6-1/8 or 6-3/8 OD at lugs.

I have no idea what I need here....Don't know who has done this before sourcing the parts from a warehouse instead of from an actual transmission, but here is the catalog I am using, and all the parts seem to be on pg#308 of the catalog.

[ame]http://www.kingomatic.com/documents/KOM_Automatic_Trans_Catalogue_2008.pdf[/ame]

If anyone can give me a hand that would be very very much appreciated

Thanks!
Matthew