Didn’t see this thread, can confirm that a transponder bypass module, like the one linked by Pilgrimsmaster, works great. Super simple devices, fairly cheap, too.
I talk about it in my post here:
CaRFID - Custom Ignition Switch Replacement (Open Source)
It’s a long post, but the relevant section is under “Security bypassing”. The device is incredibly simple, just needs +12V and ground. The antenna loop is fairly forgiving on both the key end and the ignition end. I just threw my original unmodified key in there, and hid the bypass module super deep in my dash (~12 screws need to be removed before you can get to it). This gives the ability to easily restore things to normal, if something goes wrong. Just grab the original key back out and you’re good to go.
As that section talks about, you’ll likely also need a method for bypassing your steering lock. I just cut the end off of a spare key, left it in run in the electrically disconnected ignition switch, and that worked a treat.