IIRC, the 2001s still had the old 'Delphi Electronics'-branded radios (display info is in a square area in the top LH side, instead of all the way across like the units in our 360s. I don't know if those were serialized the way that ours are to the BCM, or if one of ours will work on a non-CANBus vehicle. And even if the '01s have the CAN, I think you'd need to put in the S/N (meaning you'd need something on the level of a Tech2 to do that).
If he's keeping the truck, and has a BT-enabled smartphone, I think I'd just get a new HU. Lots safer vs. using handheld, too. No SWC to worry about on the '01s, so if he didn't want to cut harnesses, just a simple adapter harness would be all he'd need. And he might not even need that, if there's no CAN - the wiring s/b pretty simple.