j heads..more perf. questions

Without knowing the ability of the shops, it's all a guess. So dealing only with what the engine is telling you thru performnce...
My experience with Comp XE cams is they should work fantastic with that setup, 2.02s and manifolds included. a 360 can make very good use of 2.02s, and rarely have any loss in low end because of the 8% longer stroke. Was any porting done? It's much easier to harm low rpm performance by porting than build high rpm power. Also, one of the easiest ways to hurt low end is old valve and seat grinding equipment. So, I'd concentrate on timing curve and tune up. I'm assuming a stock factory balancer was re-used. That leads to the possibility of the outer ring moving. In any case, new or old, TDC should be verified on any balancer. It's easy. Using a piston stop available from Summit, or made from an old spark plug and bolt/nut, bring the engine around to about 45° after indicated TDC. Thread in the stop, so it sticks down into the chamber and lock it. Turn the engine backwards (CCW) gently, until the piston contacts the stop. Then, using a marker or paint, mark the balancer at the "0" mark. Then, turn the engine forward (CW) around until the piston contacts it again. Mark again. pull the stop, and measure between the marks. Exactly 1/2 way is true TDC. It should be the factory mark. If it's not, remark the balancer for 0, and reset your timing to what it should be. On the timing, I'd think initial of 12-14° would be fine, with a total (without vaccum..unhook and plug the hose) of 36-38° should be close. After timing is set, reset your idle and carb mix using a vaccum gage. Then take it for a ride. If it doesnt bog spit or sputter, it's time for carb tuning, which can be found in a bunch of write ups, from Hot Rod to HP Books on how to modify and rebuild your Holley carb. The manifolds are holding you back a little, but it should be enough with the stall and gearing to spin the tires.