When you’re merging MHS with found parts are you machining things down/adding threads or is it more pressure fit/adhesive type work?
For the emitter, I reused existing holes in the canon flashbody and enlarged them to fit4-40 screws. I then used some thin nylon tubing (sold as ‘blade diffuser’) to space out the emitter threaded end into the canon flashbody so it was snug and centred. Then I drilled and tapped the emitter to match the canon flashbody and screwed it together.
Ideally I’d thread the canon flashbody somehow but I don’t have the tools or skill to machine a threaded insert so screwing the two parts together using small machine screws was the best alternative.
For the pommel, the canon flashbody has a j-lock lower section that sits nearly flush with the bottom of the clamp. I drilled and tapped two 4-40 holes and inserted threaded rods that were then epoxied in place as there was no room for nuts or a screw head. These threaded rods were inserted into the Roman Props balance pipe and secured with nuts.
From there I cut the threads off the MHS pommel 12 and used some PVC pipe shaved down to make a spacer to snug the pommel to the balance pipe. Then I drilled through the pommel and balance pipe, tapped for 4-40 and secured the pommel to the balance pipe with brass thumbscrews.
Last step was one more 4-40 threaded hole to secure the j-lock to the clamp. Unlike the Graflex, the Canon doesn’t actually clamp the two parts of the flash body together so a screw was required to keep the j-lock tightly secured to the flash body.
Hope that helps.