Pull all your fuses, clean and replace using a little dielectric on each one. Then check the back of the fuse block for corrosion too. Sometimes one of the big main fuses will push the spade back just far enough it loses a little contact and results in not being able to jolt the starter solenoid.
Definetly an electrical issue...keep ta it, you'll finger it out.
Oh, and yes, you can just short across the starter solenoid to spin it over - be sure the key is on too.
Also, triple check that side stand switch - you rae describing exactly what it will do if opened. You can short the contacts to test it (check wiing diagram to be sure - maybe it was open the connection??)
