Originally Posted by luxige

One additional twist, the auto tensioner doesn't seem to be the correct one. There is no 17mm boss or any other attachment point for levering the tensioner in a counter-clockwise direction. I managed a workaround, but it was a giant pain. The slightly larger pulley size wasn't an issue, probably because of some belt stretch. The belt is not in as good a condition as I had hoped, so I'll order a Gates replacement.
I took it out for a quick test drive and gradually worked up to some strong pulls. Seems like I'm up and running again. I did note that at wide open throttle, the tune was clearly going to let me get into redline territory. Maybe that's a bug of that particular tune. This car is mainly for commuting, so it shouldn't be an issue if stay alert.