61 Apache questions

[HerrOtto]

Hello I own a 61 Chevy Apache step side short bed pick up truck and have some things I would like to improve on the truck and would like your feedback on them. The truck is pretty much original, 235 CID 6 cyl , 3 spd moved to the floor, drum brakes all the way around and original suspension. I would like to eventually add disc front brakes, drop in an 8 cylinder and an automatic. Would it be easier and cheaper for me to just go with a different frame already with an 8cyl, front disc and automatic or try to work with the original truck? If you suggest a different frame, which one( what would fit best)? I am not looking to make this a race truck just a little more get up and go.
Thank you