Being very comfortable with doing BS 50-50 really helped, takes a while to wrap your head around popping and shifting your weight being you but once you do it opens up a world of tricks.
The 1 tip that helped me off Slap was to think of it was doing a nose manual on the side of the ledge, that way your weight is over the truck and you can hold the grind. Thinking of it as a crooked grind and shifting my back foot in usually results in sticking since my weight is more forward (over the nose) when it should be further behind.
Now if someone has tips on doing a BS 180 out of BS Nosegrind, I would be eternally grateful.