Mark,
I installed two 16 oz saddle tanks, one on each side of the original tank. I didn't know they had molded a new tank, but the extra 32 oz along with using an external taxi tank, gives me 7.5 minutes from takeoff to landing pattern. I've usually got the UAT plus a few ozs still in the tank for taxi back.
As for the inlets, yeah, just shave them back a bit. I can't see any problem.
I let Ali fly my Hawk at CA Jets earlier this month. Now I know what this plane is really capable of!
David S