I diagnosed the heater blower thing, it comes on high as soon as the key is turned to on.
They say it's a resistor pack controlling speed, but it's actually a transistor in line with the blower motor. It shorts out and the blower is on high until disconnected. Odd thing is that Rockauto says the resistor pack is for trucks with simple dial climate control, which I thought mine was, and the transistor amp is for "dial a temperature" climate control. Oh well, pay to pull out the actual part and look at it sometimes, I almost ordered the wrong part.