Hey Fender3x !
First, let me thank you for the time you're spending on my problem !
When I first glued the neck I used two clamps to hold them together (using a piece of wood with marks for frets). I tried before, and every time the gap between the fingerboard and the body was the same..
Regarding the neck's pocket, I think it has always been to big : the neck fit in it, but I don't have to use strenght.. and there are some gaps on both sides of the neck.
Right now, I'm sanding everything to "repair" small damages from the ungluing ! Then I'll take photos and try to align the neck !
I keep in touch !
PS : to remove the neck I used a thin knife, a hammer and some white vinegar oh and full weight at the end on my bass !! It was so creepy..