I blew the engine in mine over year and a half ago so here in what we did.
New block 30 over new crank, roller cam as big as we could go with stock computer,the heads where done bigger springs and all the works.10 to 1 flat top pistons block decked also. Super chips tuner you really nead to use one off these work great..Air raid cold air and throttle body spacer.....also did a 2200 stall converter and rebuilt tranny and modifyed the shift electronics to take the engine tork.....oh ya and 373 posi rear end ........another little trick that box at the back off engine behind throttle body is says vortec on it get rid off it. All it does is break up the air to make it quit. A cap off something like tire shine or what ever clamped over hole covers it up good..... ...I think that covers it