If the kicked ball in a field goal attempt strikes the field PRIOR to clearing the uprights but bounces OVER the uprights is it a valid PAT?

No.

8-4-1 A field goal is scored as follows:

b. The kick shall not touch any player of K beyond the expanded neutral zone or the ground before passing through the goal.

8-3-3 During a try, A may score two points from what would be a touchdown or one point for a field goal or safety by B under rules governing play at other times during the game.

thanks