The last bit of griptape work is to cut out the dropthroughs (from the underside, using the deck as a guide), and punch the bolt holes with an awl, again, from below using the existing hoes to align. I cleared the holes with a sacrificial bolt from the top then the bottom to make it easier to assemble. Cut against a backing to avoid scaring whatever you are working over.
I had some thoughts about being a bit fancy with the grip, but wasn’t feeling confident enough with my handling to mess with it, and like having grip over the whole platform.