I began by designing a back up plate that would hold the nutplates to bolt the smoke oil distribution manifold to the firewall. I had to cheat one hole for the manifold over by about .025 so I made sure to make the backup nutplate the same.
After completing the back up plate I decided on the location for the manifold to mount to the firewall. After doing some precision cyphering I decided on the location of the bolt holes to be about 1 5/8 above the ramp edge. The smoke tank install instructions call for the manifold to be lower on the cowling in order to prevent drips from creating more "puffs" after pump is shut off but it can be located higher if you don't mind the puffs.
Drilling stainless steel is always fun. I located the center hole and drilled the firewall. I mounted the manifold and got it aligned and then marked the other two holes with a transfer punch and then used center punches to get a good point to make sure the holes were drilled exactly in place. That is one of the caveats of nutplates.....very little wiggle room unlike using a washer and nut. So the holes were drilled and deburred and the manifold ready to mount after I install the fittings.