Call Catalina!
About 6-8 months ago, someone posted info about upgrqading your aft stainless to the new 'upgraded' stainless from Catalina that had the seats built in. (rather than buy the SternPerch seats)I upgraded my aft rails to the new built-in seat model. I want to say it was around $800. (call Catalina parts dept for actual quote) The SternPerch seats are almost $300. Installed them myself. Not THAT big of a project, although the new stanchions didn't line up with the old holes so there was some drilling/patching to be done.The backstay is a small inconvenience (on my '87 30 MKI) But on the plus side, the seats are partially over the gunwale so it actually gives more cockpit room. There's no 'leg' like there are on the SternPerch seats. And also, the new rails are designed that the stainless rail that goes right across the swim ladder entry is removed...making it MUCH easier to get in about out of the boat when using the swimladder. (I can post pics is someone wants to see them)It was an expensive upgrade, but now I have the look of a MKIII without the price (I don't have the walk-thru transom, but hey, I can't afford a MKIII!!)I can't attest to the MKIII aspects, but if anyone out there is looking to add the seats, consider the upgrade as opposed to SternPerch seats. Definitely the best upgrade I've made to my boat, hands down!!JimS/V JimmyDreams