85 Bench Seat to narrow

[85/Silverado]

I was wondering why my a$$ hurt when driving my truck for more than 30 min. Today I noticed that the seat is about 7 inches away from the inner door panel and my cheek is almost hanging over. If I adjust my rear to the right so it's comfortable the center of the steering wheel is at my left arm pit.
Is there a way to move the bench seat so this don't happen?
Everything is still stock with the bench seat.

Thanks