82 Vette trans. 'jerk'

[Rmodeler]

I think this has been posted before, but can't seem to find the thread. I have an 82 Vette w/42K miles. When putting the transmission into drive, it jerks, not a 'soft' engagement. Even idling 5-6 hundred rpm, it has this jerk. I'm the 3rd owner, and I'm pretty sure the previous owner did little to nothing to the car(-$$$), so I feel it is original. I bought it with 37K and the previous owner bought it with 26k. What do you think causes this and is there a fix for it?

 

[minifridge1138]

When I had this problem it was because my idle was too high.

2 things to check:
TV cable is adjusted correctly.
Transmission fluid is at the correct level.