9in help

My main concern was going to be the fitment. I’d had to spend a ton of money and it not go in. I wasn’t sure if the housing was 56 or wheel mounting to wheel mounting completed is 56 inches. Unfortunately the one I found on Facebook sold but after picking that axle and the gears I’d want the total from speedway comes to about $2000 to my door. Originally I was going to go with an 8.8 just because of cost but now thinking if this set up fits, spending more money might be worth it. The front end is already being converted to Chevy bolt pattern because I’m running Camaro Brembo brakes and corvette rotors, and this set up allows me to have the same bolt pattern in the rear with out drilling axles. My thought process is the time saved cleaning an 8.8 cutting it welding it changing bolt pattern and such, spending more money to get something that will take less time to get ready to go in the car might be 100% worth it. From your experience, with the axle that I linked before, any issues you could warn about or anything you would have done differently? Thanks. I’d like to learn everything possible before pulling the trigger.
As I mentioned, the 56” measurement is flange to flange so WM to WM would be about 56.5-57” depending in the thickness of your brake rotors or drums.

This width is the perfect fitment for our cars in my opinion but you have to consider back spacing on your wheels to be sure.