Doug;
    The lights coming on at low RPMs indicates a problem with the
alternator. Possible causes; worn brushes, regulator, alternator itself.
Also check the small wire(blue I think) that attaches to the back of the
alternator. What kind of voltages do you get at idle; at 2k rpm; with all
electrical consumers on? Check these voltages at the battery and then at the
alternator.
    This very well could be the source of  your stalling problem, depending
on how low the voltage gets.
Ken Lewis
86 Transporter Crew Cab
60 356 T-5 Porsche
http://neksiwel.20m.com/
Vanagon tech, pixs, O2 monitor gadget