so... what does the car do now?
ZERO chance bumping the air cleaner housing had ANYTHING to do with starting the car. however, if he connected the rod from the negative cable on the battery and touched to the air cleaner mount, THAT might have given the starter a solid ground, and allowed the start.
my bet is the shifter bushings are off... what confuses me is the click...
NSS would not have allowed the click. a dead battery will cause the starter to click...
most likely, the starter is internally worn, and needs replacement if it clicks with a good battery, if the battery is good.
a weak ground strap will cause the starter to merely click, and not start.
the pic above of the ground strap is similar to what the 79 would have, but it's shorter.
the cable will be on the driver's side.

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!