Ignition switch

I used an easy-out to back out the screws on one and just drilled the heads out on another.
Putting a little penetrating lube in there should help them back out.
They're not torqued in there incredibly tight but any thread corrosion can make it a pain in the ass.

I replaced them with some stainless socket head cap screws from ACE hardware, M8 i think is the thread, possibly M6

I drill a small eight inch deep hole in them and tap a square drive screw driver in and just turn them out.

I've yet to do one on a nissan.

I've done a few toyotas at work. Just used a die grinder with a cutoff wheel to cut slots in them and used a custom flat screw driver with a wrench attached to it for leverage.

The replacement bolts are break to torque. You just keep tightening them until the heads break off.

I grabbed the steering column with switch attached and swapping the column is starting to appear more appealing than drilling out two ignition switches. Thanks guys.

you just cut a notch so you can fit a flathead screwdriver in there. They aren't torqued very tight. There's a video/guide somewhere online I remember watching. I didn't swap mine out because I didn't feel like pulling the dash again to get to it.