In The Lurch

I just inherited my granddad’s 1969 Dodge
Dart, it has a small V8 engine and three
speed floor shift. The first time I went to
start it, I guess it was in gear, because
it lurched forward and I almost went
through the garage door. I assume some
safety device must be broken. How do I
fix this?
–
Prior to 1970, the safety device was…you!
You had to have ample live brain cells to
insure that either (1) the clutch pedal was
depressed or (2) the transmission was in
neutral before cranking. Kinda reminds
me of the 1960’s “truck stop” dash
stickers: “Engage brain before putting
mouth in gear”.
In 1970, a clutch safety switch was
added to all Chrysler products. I suppose
you could add this, but I have personally
always done the opposite on later cars (rip
it out). Why? Depressing the clutch while
cranking is murder on the crankshaft’s
thrust bearing.