If the trailer is heavy enough to need trailer brakes, you need a class 3 or 4 hitch, class 5 is a new one to me, but I tow skidsteers and the like with the one I linked above.
I believe the thing you have to get out of the way is the original pintle hitch bracing, as swinters posted above, but that hitch has a limited load capacity, and is higher from ground than you want for most trailers. If you intend to haul military trailers speced to that class of vehicle, keep it original, otherwise you need a frame mounted receiver hitch.. You can probably figure how to have both, but it will require more work than cutting the support strap out of the way.