In my humble opinion (and I've been there / done that) . . . Unless your mission is going to the drag strip chasing 10ths of a second on your time slips, I would stick with the performance improvements you'll gain with a 65mm supercharger pulley along with those other mods you outlined.

Going stacked or with a 62mm supercharger pulley, either of which WILL require upgrades to the fuel system (many who have tried it still can't get it quite right) is just not worth the additional effort and expense. As you may know, I have two SRT6 roadsters. One has the Needswings DCAI, a 62mm supercharger pulley, upgraded fuel pump and fuel pressure regulator, Needswings catless downpipes and a Eurocharged tune. The other has the Needswings DCAI, a 65mm supercharger pulley and a Eurocharged tune. Both cars are very fast and fun to drive. Frankly I would have trouble detecting a "seat of the pants" difference in the acceleration between the two cars. One of these days, I'll have my son hop in one and get in a few side by side runs.

Just sayin' . . .