The GSX is probably pulling real low 15's, real high 14's stock. Adding a bigger turbo and an intercooler to the car will probably drop him down into the 13's.
Regardless, I don't think your performance enhancement plan should change. Driveline first, like it was pointed out, a PI Stallion converter and 4.10's along with a shift kit can easily knock tons of time off your 1/4.
You'll need the engine mods to play with the Eclipse and WS6, just know the girls will all like your drop top better.
