Rzr xp4 turbo apex swap engine mounting

[Hillbilly]

Hello everybody. I just tore a Yamaha apex snowmobile apart and I’m about ready to start fabbing up the mounting system for this thing. The Yamaha was in a stand alone setup. The gearbox was hard mounted to the chassis with the engine on four rubber mounts and that’s the way I’d like to build this too. 

I ordered the secondary clutch from STM but it hasn’t arrived yet. The Yamaha secondary slid about 1/4” axially and I’m assuming that was to tolerate the fluctuation from the engine moving in the rubber mounts because of torque. I don’t believe the stm clutch has that slide action. 

So my question is if I was to hard mount the rzr gearbox and leave the apex engine in its original mounts would the fluctuation from the primary under torque be bad enough to make the belts too far out of alignment ? 

I’m not a fan of hard mounting the two together like Polaris does due to no ability to adjust the clutch alignment and the apex is sitting with fresh mounts installed in my garage as it sits. If I went with the rubber mounts that it already has I could be fabricating tomorrow. I’ve seen the kits available and I’m not paying that kind of money. Everything I need to fabricate this is sitting in my garage already. 
 

Oh and the speed sensor. Anybody have to mess with this yet ? I have to assume the ratio from the apex gearbox and the Polaris gearbox are different. There’s no way I’d be that lucky