VSS tone ring or just use cv axle bolts, what would GRM do?

So I originally planned to convert my reluctor style speed sensor to a square wave for the Haltech, but it appears easier and much cheaper to set up a lipstick style sensor instead. I've seen some Vanagon folks using just the heads of the inner cv bolts to read the signal for aftermarket cruise control. Will 6 bolt heads be enough for accurate resolution or should I just buy someones tone ring that bolts in place? I'd have to drill the holes out from 8mm to 10mm but that's easy enough. However it would be easier to just use the bolts and everyone loves cheap.

Thoughts?

The 6 bolts should be plenty enough at any speed where you'd want to enable cruise control.  At highway speeds I imagine a single pickup like a bicycle speedometer might even work.

Edit: Also that tone ring in the pic only has 6 teeth, so the resolution is the same as the bolt heads. The only applications a 6-tooth wheel speed sensor would be insufficient for would be ABS or maybe launch control anyway.

Does the software expect the sensor high and sensor low durations to be roughly the same? 

In reply to AngryCorvair (Forum Supporter) :

That could be a problem, it seems most sensor ring setups only act on the rising or falling edge of the signal though.

So this won't be for cruise but my actual speed signal for the digital dash. I'm unsure what signal wave Haltech prefers but they seem happy to set calibrations for all types of stuff. I'll see if I can find out though.

I do know there is an option to choose rising or falling.

I've used wheel studs, rotor vanes, ujoints... should work just fine. 

In reply to captainawesome :

For just a speedometer even a 1-tooth wheel would work pretty well, that's how bicycle speedometers work even with lower wheel RPMs, with the only downside being a bit of lag.

I've got mine setup like your first pic for the same usage in my ECU master black with a homemade bracket, works fine, don't over think it. Those are just standard M12 3 wire inductive proximity sensors, PNP sensors will give you a switched + signal and NPN will be a switched -.

Sweet. You have been super helpful gentlemen. I shall give it a go soon enough!

For Racelogic traction control, I'm picking up on the backside of Wilwood rotor hat bolts (8) on the rear and only using 4 inner hub bolts for the front as the bearing play causes issues under lateral load on the hat bolts. Works fine for me.