6v vs 12 v glowplugs

I bought a setup to allow momentary switch use for the power to the glow plugs, instead of the standard factory automatic system. My '86 6.9 has the factory called for glowplugs, 6 volt, right? If I hit the momentary glow plug switch, it will send 12 volts to the plugs and most likely would burn them out after 5+ seconds of 12v power? Now if I replace the 6v with 12v glow plugs, this should allow standard 20-25 seconds of momentary switch time for 12v power to the new 12v glow plugs, right? Is this what folks refer to as upgrading to the 7.3 glow plug setup? This is really basic I'm sure, but never hurt to ask you folks with the knowledge out there, thank you. I have recently installed the momentary system on my '96 7.3 PowerStroke, and am liking it so far...figure it save wear n' tear on the GPR and glowplugs. My GPR on the '96 went out on me, so when replacing it went to the momentary switch for power...