Well, your Chevy is probably quite different from my Blue Bird. My steering wheel is 18", and as much as 25" off the floor, depending on how I set the tilt.
At the moment, I'm using a driver seat from a late model Hyundai Santa Fe. It's mounted on an aftermarket swivel pedestal of the type that was probably big in "custom vans" in the 1970s -- found that on eBay.
I swivel the seat around, but I have to get the fore-and-aft position just right to do it. In fact, it works best if I slide it forward WHILE I'm rotating it. The seat back must also be somewhat upright for it to swivel.
So it's tight, yes. But I do like the swivel, so we can use the seat when we are camped. Take another look at your seat, and see if you may be able to re-position the pivot point under seat, so the seat swings in a different arch.
But I'll tell you what... The most comfortable seat I own, when the trip gets long, is the original seat from my first bus, a 1982 IH Blue Bird!