The mod is the exact same for the 68-72 Nova as for the Camaro. I did it on my '70 and recently did it on my 71 as well. I have not driven the 71 yet, so no verdict on thatone, but my previous 70 handled really great! I had a bigger sway bar, poly bushings, stiffer springs,etc and it was like it was on rails. My 71 seems to drive even better after the new front end with poly bushings and all, can't wait to drive it with the G-mod.
I'd say go for it!
Good luck,
Bill C.