If I cut the growing tip off a pumpkin vine, how will that affect the pumpkins which have already developed on that vine? I don't want to do this but already am having space problems.

On another pumpkin, if I cut a whole vine off the plant, how will that affect the remaining vine? Will it still grow and bear fruit OK?

I can see I'm going to have problems with the pumpkin plants getting too big. I'm training one on a pathway and up the driveway, the other is going out into the alley behind the house. However, one is headed for the street. Help, I need a "Pumpkin Crossing" sign. Ha ha!