Hi. If you have a ZT-260 you do indeed have the two way valve which COULD be replaced by a Y-piece. I think they are available from X-part though. If you have a R75V8 you can't do it that easily. It's a two motor 4 way jobby and handed, LHD/RHD, to boot. They are available from X-Part, I just bought one, since the motors on mine have a mind of their own and jam on the plastic tracks which activate the two valves.

David