Depends on the opening time of MK, I'd say. If they don't open until 9am, you might have a tough time catching a bus to MK, then mono to Poly. With an 8am opening at MK, though, I think you'd be fine.
If you decide to bus/monorail, I'd plan on...45 minutes???
Solana Villa 3/11
Grand Floridian 12/09
ASMovies & Grand Floridian 3/08
AK Lodge 3/05
ASMusic (Honeymoon) 3/98
LBV Villas 6/83