What do you think?

Ok, I want to get some opinions here. I recently bought my 7 yr old his first truck, a 1950 Chevy.  I want to build him something that will be mild in the power department, looks like no other advance design truck, and will carve a corner like an F1 car.
 
So, here's my plan: Box the stock frame and add cross members, add IFS with C5 Corvette parts, ford 9inch rear with triangulated 4 link, full roll cage w/ race buckets and 5 point harness, and powered by a 4200 GM overhead cam inline six.

Chassis wise, I think with the right components it should handle, my grey area is in the motor. I can't seem to find squat for the 4200 inline six as far as performance goes. I want that deep and mean sound, which require a split header that nobody makes.
Anyone have any suggestions?