Thanks everyone. It was Chain of Rocks Fun Park, not the Highlands, which were already gone the year before I was born. This park sat on the river bluffs and was operating until about 77 or 78. We have a Yahoo group trying to map out a recreation for the park and this question came up.
This place had the scariest ride I've ever been on: a ski-lift style skylift that went out over the bluffs. It had a 20 foot loading platform that ended at a 60 - 70 foot drop. You would stand on a yellow line and wait for the car to come by and smack you in the back of the legs, then sit down and pull the bars closed. The cars were fixed to the wire, so they didn't stop for you. I was always terrified I would miss the car and be swept over the edge.
Jeff