Hi CaptainOC
I'm not with Laminar Research, just a fellow simmer in the UK, but also a qualified computer technician who builds his own desktop PC's.
Without knowing your PC's full specification and operating system, it would be difficult to offer any specific advice, but in general terms, I would comment as follows:-
1. With regard to your 1TB SSD drive (your local C:Drive) you haven't said what problems this causes for X-Plane 11, but I can't see any reason why the software cannot be successfully loaded on this drive, unless there is a capacity issue?
2. As far as the two regular hard drives are concerned, is there any data on these that you need to keep? If not, then simply reformat both drives to a working NTFS file structure and try reloading X-Plane 11 again.
Sorry, but not sure what more I can offer without much more detail?
Regards