Building a Rhodes harp

[hogdog42069]

I'm modifying my 54 key Rhodes to go down to low E like the 73 key ones because switching back and forth is driving me crazy. I'm making a new harp and key bed to preserve all the original 54 stuff on the high likelihood this turns out terrible. I built a new key bed out of a spare 73 Rhodes (plastic keys). I made the frame for a new harp but am having an abnormally hard time getting the tone bar mounting holes nice and straight/ aligned with eachother like they are on a normal Rhodes. My process is just going through individually and mounting them so the strike point is centered on the hammers. It was around the #22 tone bar I realized consistent forward placement is important too for uniform hammer smacks. So that's been resolved on the remaining tone bars.

Originally I took some paper and poked holes in it along where the drill pattern was on the 73 I took the parts from, but those points didn't really line up exactly with the center of the hammer tip on each key. So now doing each individually.

But am I an idiot? (yes), but am I missing an obvious way I should be drilling/ installing these tone bars? How would they have done this in the factory? It's taking forever forever to do also. Thanks