since you have needed to fool with the shift lever position for some time to get it to start, I would suspect the neutral starting switch. This switch, just aft of the modulator on the left side of the trans, inhibits current to the starter solenoid unless it senses that trans is in neutral or park.

__________________
'82 300SD - 361K mi - "Blue"

"Good judgement comes from experience. Experience comes from bad judgement."

listen, look, .........and duck.