Stan, only if you make it illegal in Vintage; electronic fuel injection will do it & so will OHC.
Others have asked why smaller cube GMC can't run in the smaller classes. The reason is XXO and XO are 0-325" and not divided as "normal" engine breaks. But as answered make them illegal for Vintage and your OK.
My typical response to the limit of "modification" is if you can bolt on the stock manifolds and they can seal your pretty much OK. This is why there are 2 different classes. Good Luck.