I really hope you aren't serious...but if you are, I can't let this opportunity to be snarky go by the wayside.
It's easy, of course, because AHL quality rinks don't even approach NHL surfaces.
All they have to do is melt the ice, soak up over 30,000 gallons of paint and water (Carrier Dome most likely does not have the proper drainage), disassemble the stands, disassemble the protective netting, disassemble the glass, Disassemble the dashers, penalty boxes and benches, remove the base (multiple layers of wood and interlocking heavy rubber panels) and then put up goal posts, rewire the electronics and communications, and vacuum the carpet for football.
It took 5 days to set up hockey. Considering these are probably union jobs, you may want to add on another 36 hours. Oh and pay for all the labor and reimburse the promoters, owners, and universities scheduled to play. Yeah, it shouldn't take too long and it's probably pretty cheap.