th350 to np208 tranny adapters HELP!!

[mud slut 350]

so im trying to trade a np 208 and everything but a turbo 350 to convert from a 4 speed to a 350, the guy already has a trans, and in return he will give me his entire 4 speed sm465 setup. the problem is he has a trans and i have the t case but no adapter between the two. because i dont have a trans to swap straight up with him im gonna buy an adapter for him. I need to know how many adapters there are out there for the 208 and what ones will work with what 350-208 combos. also i will be giving him the crossmember too so does the height of the adapter depend on the crossmember? if so i would have to get a tall one correct? and also ive seen at least 2 different lengths of adapters im waiting for a text back from him to find out how long his output shaft is then i will post that too. until then this is all the info i have. any help would be great!