i am debating between an atlas 5.0 for $2636 with the adapter, or a stak 3spd for $2775 with no adapter, but delivery. the atlas i could pick up so there is no delivery charge. my only concern is that i dont know enough about the stak4x4 box. i dont know anyone who has one to ask questions, so here it is?? has anyone experienced any problems either during install or after the fact? i am leaning toward the stak box just because it looks like a good product with an extra speed over the atlas for only a couple hundred more. if you have one, what tranny are you using and did you need the adapter? the other thing that concerns me is that nobody can tell me if i need the adapter or not? i have a th400, with the atlas i need the adapter, but with the stak4x4 box, i may need the adapter and an output shaft on the tranny. nobody seems to know what i will need... that is the only reason i am second guessing the stak4x4 box.... noone seems to know what i need.. any advice?