Hi Dave
I thought I would pass along some info that I have on the Apex so far.
There are a couple rollover valve kits out there on Apex's so far. I have personaly done one install on a S/C Apex. The pics on my web site are from this install.
Plans are in works for installing a roll-over valve on a stock Apex as well. I hope to get feed back from that installation as the season progresses.
What I can tell you is the wiring harness, tether, and LED will all fit the Apex. The plug and play connectors fit, and the system functions correctly.
The breather hose on the supercharged Apex is 3/4" and I have a few valves that are sized for the 3/4" hose. Your MCX kit may use 3/4" hose as well.
On an Apex, the valve needs to be installed in the hose that runs from the crankcase, to what would have been the air box. This hose may be routed down to the belly pan now and may have some type of filter on the end. This is common on most boosted kits, since there is no longer an air box!
The hose that runs from the crankcase, to the top of the oil tank is the oil return line. Do not install the valve in this hose.
The shut-off valve can be located almost anywhere in the breather hose. Although it's best to have it as close to the engine as possible. To reduce the amount of oil stored in the hose. The valve performs best when it is mounted at an angle, with the solenoid end of the valve is angled up about 45 degrees. This allows the oil vapor to drain from the valve quickly during normal operation, and helps provide a fast response time during valve closure.
Because the valve is mounted up by oil tank on Nytro/Phazer's, it very easy to position it correctly for best performance! With an Apex things are a little tighter under the hood, thats one big engine in there! Less room to work with in certain areas.
If you have some pic's of your MCX breather set-up, I may be able to tell if there is a good location for the shut-off valve to be mounted.
Bill