Did this today. They are Iggee leatherette (vinyl) seat covers - not full upholstery. They install over the existing cloth seats. Got them directly from Iggee through eBay for $125. Will just show the driver side.
The driver seat is getting a bit tatty.
The bottom cover is held tight by six elastic straps that hook on the bottom of the seat pan. Then a drawstring-like cord ties in the back. I routed it through a hole in the seat pan. This photo is before I was quite done tying things up.
The back cover is held tight by these big velcro flaps. Installation is an exercise in trying to pull them tight from both sides while sticking the velcro.
Pretty much done.
Back in the car.
For a slipcover, these are amazingly nice. You can tell they're slipcovers if you're looking for it, but when sitting in the car it's just like the seats were meant to be that way. No more tatty seats!