I discovered an easy connection for starting my '72 van from the 
engine compartment.  In center of the "computer Plug in thing" there 
are 2 large connectors which are horizontal (the largest on the 
unit) and above that are 2 more connections that are verticle (not 
quite as large, but larger than most of the connections). If you 
jump the 2 verticle connections you will turn over your engine.