that is grt news, and no, in those days no aluminum blocks, heads yes, blocks no. 100 lbs difference is remarkable...my Camaro ran in gas B class...and if you remember a guy named Norm Paddock, Opel GT, later Pro Stock...and a guy Glidden....I worked for Norm in the evenings, and Glidden did my head work on the big block chevy...he liked Fords better...lol...but did good work until he got his big break...Norm is now in FL...Bob is still in Greenwood IN....I worked and ran in some fast company in those days..anyway the point is, it is fun to watch someone do something different like a build you are doing...you just don't see this anymore...good luck...