Yea that's possible too, getting the 60 and 60e mixed up. The trans I have (the 4l60 lol) was out of an 89 silverado, which as you mentioned was the 88-98 body style. Which is great because I was able to couple it with my 89-90 TBI setup from Howell Engine Developments. So the two are working together through the ecm. I very much like.
