At 330 hp there's no reason for "better" rods. The factory rods are plenty good. You can get a half a point of compression swapping from a .040" head gasket to a .016".
If your Vortec heads are good, I'd stick with them.
Get the spider for holding down the roller lifter dog bones. Use it as a template. Drill and tap three holes, insert all-threads, and jam-nut them in place. You now have a mount for the factory roller bits. Then use a cam button on the nose of the cam. Bam! Cheap roller cam. Note that I haven't gone back into my TBI motor to do this yet, but it's my plan.