For those of you who have accomplished this. How maticulous did you get? I'm just a hobbiest doing this, and still know of some imperfections such as stock GM ripples on the wheel wells. I would assume that the top of the frame rails, wheel wells, struct caps and fire wall are the main parts which will be observed once the motor is installed.

any tips on achieving a great finish is appriciated. I've been using a board sander for the frame rails, and the 3m foam "board" sander for all the round areas. I use 80 grit on the filler at first, and then follow with 180.