you have a nice truck lose the tb spacer and i would go back to stock maf. if you want a quick dd, lt's, 3000 stall, shift kit, good tune. your truck is light. i envy you. anything else can be compisated in spray and sticky tires/caltracs.
forgot about the cam.. get a 220/220 on 112 or 114... you'll like it. it's like a standard.
02 Sierra... motorless for now.
02 SS.. stock bottom 4.8, 241's, 224-220/116+4, 918's and pushrods, front mount turbonetics 78mm, HKS GTII, TiAL, eBoost2, Yank PT3600, Performabuilt 60e, solid motor mounts. Tuned by me with HP Pro and LM2/AFX