Bottom reinforcement

I got an old polarkraft tunnel hull aluminum john that's bottom is dented and scratched pretty bad from running over the rocks located on the bottom of the local river. I'm repowering with more horsepower and wanted some opinions on reinforcing the bottom rear of the boat. This is what I was thinking---- purchasing about 3ft lengths of aluminum sheet and having it glued and welded to the rear 3-feet of the boat (where most contact with the bottom occurs). If I did strips between the ribs and out to the chines do you feel that would be time/money well spent? Or because the ribs would not be reinforced do you feel it would be a waste of time? I have a buddy who will weld for free but trying to bend over the ribs on the bottom will present a problem.
Appreciate all opinions.

Bending over the chines sounds very hard to do plus you will be capturing water between the 2 floors and that will stay wet and cause premature corrosion. If it is not leaking, I would leave it alone.
Tim