It really depends on what transmission you want, and what you'll use it for. If you drive the truck on the highway a lot, an overdrive gear would make a bigger differance than the auto or manual difference. Newer chevy's came with a 5 speed stick, but those probably aren't too pleantiful in the junkyards yet, and you have to be careful shopping for an overdrive auto, since the earlier years of the 700r-4 auto aren't too reliable on their best days. My stock one went out at 60,000 miles, but I had a performance rebuild done on it by a reputable local tranny shop, and it works GREAT now. I was getting about 13 mpg around town and 15 on the highway, as long as I drove with a light foot.