Yes, you can alter the front rest. I’m not too keen on altering the fore end either. I just noticed you’re from Drummondville, home of the Dionnes, Yvan Cournoyer, Yvon Lambert, and others. Have you ever heard of Ste. Petronille, Ile D’Orlean?
The rules say, bag filled with sand. You should be able to get a flat bag with ears set up for 2 1/4 inch fore end. The rules also state that the rifle must not be locked into the bag or that it must be lifted out of the bag, but then you don’t want it so tight that the fore end is too tight...
I’ve used the hot iron a couple times, as well. And it worked both times. I will say it’s a bit scary when all of a sudden it releases. I had no paint damage.