Please send pictures showing the issue you're having with CrossFire. And if you can, a link to the installation instructions.
Also, what are you trying to attach the system to? The Wheel, the Axle Hub, a Wheel Simulator, a Wheel Cover?
I don't like the idea of valve extensions fastened to the part of a Wheel Simulator that covers the Axle Hub. Why??? If the Simulator comes off, it'll rip the extensions and/or tire valves apart. Or, extensions'll hold onto the Simulator and let it beat up the coach body.
But many rear simulators and front wheel covers attach with threaded fasteners. Our Dicor sims do, and at least some of the Pacific Duallies do also. In THAT case, you can probably fabricate something that attaches to the hub-covering part.
Personally, I think you'd be served as well, probably better, with custom valves like the
Borg Dually Valves mentioned above, plus a TPMS kit. You'll see what's going on right from your cockpit. The Borg valves are now available through Camping World. There are often sales, coupons, other discounts.
I, by the way, was a holdout when it came to custom valves. Finally got a Borg kit, and now I'm happier than the proverbial Pig in Mud. Can't recommend them too highly!
