Looking for a few accessories for my new to me 1500. Currently have the solo seat and I would like to pickup a backrest and rack for the solo seat. Will a k53020-311 and k53020-320 work for a solo seat or is that only for the 2-up seat? If it won't work what am I looking for, any PN I should be searching for? I know none of this stuff is in production anymore but it helps if you can narrow your search. :) Thanks