Hi Frankie, that link to FU Tone posted bu Simon shows what needs to be done when top mounting as you either need to fill the deep PUP mounting leg holes with something or use a bracket.
I shaped up some timber to the exact shape and depth on the EX-1 and wished I had seen these brackets or at least had the foresight to think it through a bit more as what I did was very fiddly and too many multiple attempts to get things close to where they needed to be. On the Toneriders they now have 3 screw holes on each leg, the original one in the centre and two more above and below so that I can adjust to the right height and angle. If they get swapped out at a later date no trouble reverting back to using PUP mounting rings as using normal wood screws strips the thread and no longer able to use the fine threaded PUP height adjustment screws.
Cheers, Waz
Edit:
Try zooming in on this shot as you may see the black screws used, just either side of the shiny metallic bit in the middle which is the empty original screw hole.
You will still need some high density foam underneath as they do end up sitting quite high out of the body and it just helps with the fine height & angle adjustments.
I can take some close ups if you want to get a better look? Just let me know.