In reply to Rog Wilko:
Also a small car park that often has space at besses, and nearby street parking if full.
But, given the last bit of motorway is likely to be your biggest problem, have you thought about train in from Horwich Parkway or Lostock? That train line used to be one of the quicker and more reliable ones but I don't have any recent experience so keep an eye on the voting buttons and listen to anyone more qualified.