The 7.5 will most likely stand anything the 2.3 can dish out, na or turbo. My 7.5 stands 1.9 sixty foots behind a sprayed 5.0, C4, setup. (Yes, I have an 8.8 in the garage)
I would not worry about the rear with the 2.3. The 8.8 is significantly heavier also.
If you go 5.0 with big power, a stick and slicks, yes, you need an 8.8.