Killer B,
In your first post, you said you were looking for "inserty things and washers". I didn't have any luck with beveled washers, but you can see what I did on my El Cheapo Build-along. You can get the inserty thingies for about $1.05 from Lowes in brass, and I found the proper beveled flat cap screws from a specialty bolt/hardware store here in Augusta for 0.50 each - oh, and also able to get the guide pins for a quarter a piece. Could not find the bolts at Lowes or HomeDepot though. I made my limbmounts like a ChekMate, with the bolts flush in phenolic. I like the look and they haven't blown up yet! The threaded inserts are a little different, with thin self tapping threads. I drilled the hole the size of the insert body, then I back bored a little larger the first 1/8" or so to help the threads bite. My build along describes how to use a bolt, nut and rachet to drive them in. I used the drill through method with an overlay versus the Bingham drill jig. Here's a few photos, plus you can do a PowWow search for El Cheapo to find the build along. As to beating points out of masonry nails...you're on your own!
Here's driving it into the riser:
Finished insert and pin:
Finished limbmount: