Regular or Short sleeve for broad chested tux?

So I'm standing in a friends wedding and ordering a tux online for it. 5'8" with a ridiculously large chest, combination of simply born with a larger than normal ribcage and a 300 pound bench max. Currently 176 pounds, but overweight from coming off shoulder surgery and will be back to my athletic 160-165 pounds by September. Chest wise, 44in fits a little snug but doesn't look bad, 46 is ideal around the chest but ends up needing a lot of work to take in the sides and the bride/groom were kind enough to find affordable Tuxes for us so I'd rather not spoil that if I could buy online and simply make minor altercations or preferably none at all (Note, note exactly sure how normal tux purchasing works. I'm a new hire engineer trying to do this on a college budget.)

My question is do I want a 44 short or a reg at 5'8"? my arms and torso are pretty normal sized, as far as I can tell. Site doesn't give a suggested arm measurement for determining if you should use which version.

I'm 5'8 and wear a 38S or a 36S/R. You definitely don't want a 44R. It's going to be inches too long.