These trucks used Chrysler's electronic ignition. So if you have spare parts for other Mopars i would take them with.
300 miles in a truck like this will take you a long time to get home. I would guess 7 hours. Maybe more. Think 50-55 and lots of gas.
Yes it has electronic ignition, so spare ballast resister and ECU will be in the parts bag. It's about a 6 hour drive in a regular vehicle so if I can do it in 7 that would be great, the good thing about the drive is it's all two lane rural so I won't have to worry about winding it up too much until I get back to Boise and turn east, then I have about 10 to 15 miles of interstate to deal with and then drop back off on two lane again. I will also bring two five gallon gas cans with me, I would assume it will get about 10-12 mpg's!