Scott, thee engine looks good. One thing: Hope you are not planning of keeping the muffler inside the cowl? Imagine this thing red hot all the time .
Also will radiate heat into the oil pan and radiator. I have no opinion on the aluminum work. I'm a fiberglass man.
Bulent "Buly" Aliev
FXE Ft lauderdale, FL
 http://tinyurl.com/dcy36