Just to update-
I did recoat the horn ring, the original coating had crumbled off. I also got the coil installed. The end of the shaft on the crush can is beveled to help start the coil. The key is to get the coil started evenly (square)using a flat surface across the coil. Then I actually used a fork that just luckily fit across the circumference of the coil-made contact 2 places 180 degrees apart. It tapped in to place easily then. You cannot use a round socket because the tang that trips the signal switch is in the way. If you had to do this a lot you would need to make a special tool for this job.
thanks again