I have a factory arctic cat 2-up conversion seat. It is the same length as a single seat and fits the ETT tunnel. It is a one piece affair including gas tank and seat. I usse this on a 98 ZR600 EFI, but it could be used for a carbureted sled because it has the threaded nipple on the front to the tank where the fuel pickup goes for the carb sleds. The EFI pump cutout in the top would just have to be plugged which could be done with a plate. It is the one on the ZR in my signature. I was getting ready to post it on e-bay. If you would like it I would sell it for $175 plus shipping. PM me if interested. Below is another picture.