I know that it sounds simple: you glue them in, right?
There are a few things that need to be considered. Without some sort of support the bolts will not stand straight (as you can see on the left):
After a few ( a good FEW) trials and errors I have settled on this template:
Well, that took the whole morning. I'm using recycled aluminium printing plates for making templates.Now I need to cut about 25 of them, and precisely drill the 4 holes in each one. That will take care of the afternoon.