904 low gear- which vehicles and which internal parts?

I've ordered twice from them. 1st time everything went perfect. 2nd time I had 1 small issue with them. I needed a speedometer housing and I did the internet order thing and it showed they had it but when I got the order it said out of stock on the invoice. Luckily I was able to file the threads on the old one and use it but I would have much rather paid the $3 for a good used one rather than file threads for 20 minutes. From now on I'm going to call my orders in to make sure they have everything in stock.

They have a few new parts too but I believe their main service is with used parts. I just bought a set of 4 pinion planetaries that they refurbed and they looked like new.

Ok, I hear you on the input shaft and output shaft thing. I guess it looks like the only way I will know is to buy the damn thing and find out the hard (I really hope it is a low gear and will work).

As for the parts place, I will definitely use them in the future if I need hard parts- im hoping this trans im picking up will have all I need to convert (I already checked that website for late model A-500 pump gears but no luck and I know the trans I am looking at does not have the pump gears I need either)