ive got two kits that have the center mount. but i like to play one up and want the ride cymbal over the bass. here is what i use.
you can find a 60's ludwig disappearing spur mount. this mount was also used on some clubdates for the disappearing cymbal mount. it accepts a 3/8 rod which is the same as the upper cymbal rod on a ludwig 1400 cymbal stand.
anyway, the disappearing mount will sit down inside your bass mount. but, it needs to be a little longer to hold properly. i couldnt find a coupler with the exact threads. but i found a galvanaized pipe coupler that threads on enough to hold. then, i wrapped the coupler and threaded portion of the disappearing a mount a couple of times neatly with some duct tape. this will be inside your bass mount and will not show. this is done to get the fit just right. then, you simply use your knob on your bass mount to tighten it up.
gibraltar makes a z bar that is around 13 bucks or so i think. it will mount in the disappearing mount and locate the ride cymbal enough to the right so that even a 22" cymbal won't come in contact with your ride tom. it works perfectly and is fully adjustable as well.
here is a pic of the setup on the bass drum of my vistalites. hope this helps some. its easier than i made it sound.
mike