alright, with all the time that you spend wiring the aftermarket dash with switches/gauges/lights etc. you can reuse the stock dash for 1/4 of the price and half the time.
1. Go down to the local auto store and buy the big fiberglass repair kit, a few hose clamps and a sharpie.
2. mock up the vent assembly to the cage and mark it up with the sharpie, take the
vent out and place on the ground.
3. separate the wiring harness from this and cut away the previously marked spot.
Check for clearance issues and adjust accordingly.
4. Now fill it in with fiberglass. Dont worry about what the fiberglass looks like, you
will never see it.
5. reinstall the stock dash with whatever bolts will fit, and whatever doesnt bolt in, use
the hose clamps.
6. ??????
7. profit!