OK. Took a look at one, how about running a 10-24 tap down into existing holes about .625" and getting some RHMS 10-24 x 1.75"( plus your additional spacer) for replacement fasteners. A #25 bit could be hand twisted into the holes on my case back plate.

You might find that the spacer is not thick enough to allow use of a ball link on the existing plate secured to the throttle shaft. I chose to use a ball link so I made an additional spacer from A/C plywood laminated with expoxy set between two pieces of glass.