My next batch of guitars are going to have bolt-on, adjustable necks and elevated fretboard extensions supported similarly to archtop fretboard extensions (does that description make sense?), i.e. the board won't be glued to the top, so I won't have the issue of a hump at the body joint or anything like that. I'm planning to install the frets in the board before gluing it to the neck. I might hammer them, but I might go ahead and get an arbor press (putting the cart before the horse, I already ordered John's set of cauls) and press them in.
Assuming most of us use hammers here and there even if pressing frets, here's a little tip from my class with Sergei de Jonge - try a small dead blow hammer with
interchangeable faces like this:
For me, it works infinitely better than the Stewmac hammer I'd been using. I got this one at
http://www.hammersource.com/Dead_Blow_Hamm.html
and I use the "hard white" (nylon) face. It's the 1 lb one with the 1 1/4" face.