I'm considering swapping in a th400 into my blazer and want to know how easy a swap it is. Right now it is a th350 and 205 setup. If I got a TH400,adapter and the mating 205 and even the crossmember could I just drill new holes in the frame for the crossmember or would I be better off using my stock crossmember? Since I'm going with a 14b FF if i used the drivelines from the th400 said truck would they all bolt to the 14b without the conversion joint. So I would just have to get the rear shortened and make the front longer. What other issues will there be? The other issue is I plan to go with a doubler in the future as well as a bigblock. For you guys that have put in bigblocks have you moved the motor forward at all? Seems like that would help with the distributor clearance, driveline angles particularly with a doubler. I will have around a 6-7" lift in the back with a doubler setup would my driveline angles be too extreme? Also with the double from ORD's site it looks like I would need to get a np203 th400 for the shortest adaption. I'm trying to plan for the future without have the frame full of crossmember holes but maybe I can't avoid that.