Parts list for warner electric lift?

I have a 1973 John Deere 110 lawn tractor with a warner electric lift that I bought that had the lift removed from tractor when I bought it. I was able to repair the problem with the lift motor. But, when I went to install it on the tractor I found a spring that is approx. 1 1/4" to 1 1/2" in dia., that appears to attach to the lift connection point with the lift, as an assist to the lift so that the 12volt motor system doesn't have to do all the lifting. I cannot find this part because of the age of this equipment.
My question is how long is the piece that attaches the spring to the end of the lift suppose to be? And are there just two holes in the piece or is there a slot in the lift attachment end? Also what thickness should this part be made of?

Thank you for your assistance with this.