I'd start with double sided tape to see if you like it.
You could also use the shoe soles pretty easily to build up the palm of your grip. Tape it on and shoot it to see if it's for you. If not, take the tape off and viola you're back to where you started with no damage to the bow.
If you like it, glue on some wood pieces and file them to shape, then cover with whatever grip material you like.
You dont however have to do this, you can shoot a bow with a high wrist without having a highwrist grip on the bow. Case in point would be doing so on a HH style longbow.