Well, this website said that there were people who did conversions that were freeway capable using the motor, but the cars tended to be on the lighter side:
"Some have had success with this set-up in light weight highway vehicles."
AC 31 on ebay
I was trying to lower expectations possibly more than necessary, so someone wouldn't be disapointed if they bought it.
Do I know about the highlander hybrid? I know nothing. haha