eddiech: It would be shame to ditch the model. You might try adding beams the thickness of the mount on top of the current beams and run the YS without a soft mount. I would first drill out the holes in the current beams and fill with dowels. Someone said the OS 1.40rx is a drop in replacement for the YS 1.40. I have not yet been able to confirm that. That would allow you to do the same with a two stroke engine with less vibration.

I will not get a chance to run my repaired mount/engine combo until at least tomorrow or early next week.