The original scope's construction modification is minimal and easily reversible. But most likely will void your warranty. Be especially careful while handling the mirrors during full disassembing of the OTA.
Inspect the attached Google SketchUp 1:1 model file for all of the details and measurements.
Your comments are welcome!
Step 1: Major modification
The width of the groove to be milled depends on the diameter of the set screw you have. The grove is about 1.5 - 2mm deep in order to include the top narrow part of the shaft. The set screw should easily slide in the groove, but without much of freedom to prevent back lag.