Daughters 1990 lincoln mark vii has check suspension light on Now car sits cockeyed. Is this major?

It may be the mark Vii has a air ride suspension I belive and depending what the issue is it can be. If it is sitting sideways it may be a leak on one of the rear bags

thinking about it it could be electronic control

He is correct... What you need to do is have the computer scanned to identify what set the light. From there, you will know what to focus on.