Cruiserdrew
On the way there
Did you check the fusable links? All ignition related fuses? The EFI relay? Those should blow and protect the system in a dumb a## move like reversing the battery terminals. That would be much cheaper than a blown computer. Those Toyota computers are made out of gold and saffron and cost near $1000. My $$ is on a bad fusable link. Just buy a new set ($12) and see if it works.