If you are experienced with the YS... then it should be fine.

I bought a NIB YS 1.20 NC a few years ago to go in a plane I was building which had hardwood rail mounts. The mounts were spaced to fit the engine and the the cowl and spinner all setup for that engine. However, I could never get the engine to run reliably so never flew it with the YS.

I'm not suggesting the YS isn't a good engine... I guess I was too stupid to know what to do to get it running well. I finally gave up on it and set it aside and bought another brand engine more suited to a sport flier. It took a fair amount of effort to rework for the different engine.

What I'm saying is... be sure that your happy with the engine before committing to it with the build.