Applying pressure to your front foot will brobably just make you pearl. Spinning a 3 on a surf style board requires you to essentially pop a wheelie and spin on the tail. You don't flatten out like on a skim style board.
Yes, driving up to the back of the boat helps maintain speed as you come around. Some big keys to successfully riding out a 3:
-Squat down, don't stand tall.
-Turn around and scoop the wake with both hands, progress to scooping with only one hand.
- Your body will go where your head goes, so look back as you scoop the wake
- Apply a bit more weight on your back foot, but also use your front foot to drive the board around.
I hope this helps. Good luck.