PO500 help, where to start?

Trans sensor(s),
Wheel Speed Sensor(s),
Cluster,
Something else

which one is going to fix this mess?

A while back, my cluster decided to give me a light show; check engine, brake, abs, and 4hi 4lo flashing back and forth. Fun to watch, but my speedo also went out; realized later my odometer and cruise too. Engine code PO500.
Read up and hoped wheel speed sensors might be the issue. Got a couple replaced, broke the third and the 4th was cracked out of the box. A mechanic fixing another issue (starter at 140K) said it was most likely the abs pump. He based that in Chevy trucks that he’s seen with the same code, but admitted he’s never done it in a Toyota. I’ve paused in my wheel speed sensor replacement for now.
I haven’t found a consistent answer about the most likely issue, but hoped somebody here might have had the same problem and could point me in the right direction before I start throwing parts at it.

 

Found at Tundratalk

 

Thank you!