I have a 93 gmt400 with a carburetors 350 in it and 4l60 trans with a little work. I have a blown front main and rear main seals I have a blow oil filter housing seal I am leaking oil from the driver's side head gasket and timing chain cover. Trans won't shift unless I manually shift it and leaks out the tail shaft. So to fix the trans should I wire a throttle position sensor in the cab so the trans is being told it is under load or should I just go with a turbo350 or 400? As for the motor is it gonna be more efficient to pull the motor and fix what's leaking and swap heads and throw a small lift cam in and call it a day or should I rebuild it and lastly should I just find a 4 bolt main 350 or a small block 400. I currently leak oil at the rate of 1 quart every 6 miles.i stoped doing oil changes because at this point the oil don't stay in the engine long enough to they dirty. And need to figure out what I am gonna do real fast. Ohh and it's running open headers.