No big deal, just take a Dremel and grind away on the back end of the port. lol
Seriously, I have opened up a few ports for the reason you cite.
One was on a 40xb which had a 308 length port. I could get a live one in, "300 wby case", but not out without pulling the bolt.
The rinky dink Rem bolt release was a pain so I removed that. But that allowed the bolt to just fall out unless it was closed when the gun was picked up and when there's snow on the ground it adds to the problem.
Another was a Hart#4 custom action, also 308 length.
I had converted that to a 30x378, but left the Rem size bolt face as a standard mag size and turned down the case rims. Actually it was an early version of a 300 ultra mag. But that action had a nice bolt stop/release on the side of the action, so it wasent as big a deal as dealing with the 40x. I still have the 40x, but it now has a Saco type side bolt release I had Bruce Baer install for me.
If you ever take a trip east on I 80, when you get to the Kylertown exit in PA, get off and you will be in easy walking distance of Cutting Edge. Very nice and very new facility with lots of nice Elk and Mule deer mounts taken mostly in Idaho. Our camp is about 20/25 crow fly miles from there. You will need a tight twist to use his bullets, like an 8 for his 300 gr 338s.