I installed the switch with no problems, and saw that it was indeed too short. I tried small rubber caps (including two that I pulled from the end of bungee cords). They worked, but didn't look good. Cutting them straighter would have helped. The sizes I tried fell off and would have needed glue anyway.
I grabbed two pieces of shrink tubing -- one about 4mm and one about 5mm, give or take a mm. I placed the 4mm tube on the actuator, which was a tight fit, but not a struggle. The 5mm fit over the smaller one no problem. I cut the length to about 8mm and very, very briefly heated them with a lighter, just enough to taper the end and firm them up a bit. Here is the result, which looks good and works perfectly. Hope this has helped someone. I'd be happy to hear about other fixes for this switch.