Yes you receive new shaped foam with a cover to fit along with a fitted cover for the stock shape rear foam so front and rear match. I've done four myself now and will say I was a little nervous on the first one but it's really quite easy. You unstable the factory cover, which is probably the most difficult part, the foam just lifts right off. I spot glued the new foam onto the base with spray contact adhesive just to prevent it from moving while I staple the new cover on.
I picked up a pneumatic stapler from Harbor Freight along with 1/4" staples for under $30. https://www.harborfreight.com/20-gau...ler-61619.html
Here's a comparison of the original seat foam with the new SC seat.
The stock seat width is effectively 11" at which point the foam slopes downward to the side.
SC foam is slightly dished so the sides raise up almost to the edge then turns down which gets you 12 1/2" width. Also as mentioned they completely do away with the forward slope. This is accomplished by slightly raising or building up the front while leaving the rear seating about the same height as stock.
SC also offers a Rally seat for the AT which is completely different, the riders seat is probably 3" taller and it includes new passenger foam as well because they lower it.
Here's a video of them showing you how to recover a seat. https://www.youtube.com/watch?v=ZdKtzdWXTeE
They'll do the recover for you for only $25 but shipping a seat base to them and shipping back can be expensive.