Since the 1968 C3, Corvette body panels have been press-molded using SMC similar to the TJ hardtop. The basic difference between SMC resin and ordinary polyester resin is that SMC resin contains mold-release, which means that after molding, ordinary polyester resin won't reliably bond to it.
Repairs to parts made in SMC and parts made in traditional polyester resin fiberglass are the same except for the resin and filler used. Non-structural repairs to SMC parts are best made with SMC-compatible polyester resin and structural repairs are best made with epoxy resin. In both cases ordinary fiberglass mat or cloth can be used. SMC-compatible body fillers should always be used.
Some people do repairs to SMC using ordinary polyester resin and depending on the particular SMC compound the original part was made from these repairs can be successful, but they are generally at risk of separating from the underlying SMC part, so SMC-compatible polyester resin or epoxy resin should always be used instead of ordinary polyester resin.