I went to super cheap and got myself a pneumatic pop riveter - it's a cheap piece of crap BUT it's great!! Makes popping 100's of rivets quick and easy, no more aching hands and feet :D I think it was about $125, well worth the investment I think.
Probably a bit late for this project though.... you've already done the tub. I re riveted my tub in a hour or 2 with it.

