Glad to help, Slavey.
A caliper, or even a tape measure should be able to give you a close enough measurement to determine if you have .625 ahead of the gas block seat.
If you dont have .625 there, you can make it work if you really want to, but it might be looking at custom work like re-profiling that can get expensive.
It might be cheaper to just get a long free float rail and a front BUIS.

