I struggled with the Catrike neck rest a LONG time. Tried a Krispie Steve. Couldn't find the right formula.
I discovered this car necl rest. I got them for the Cats and WOW! They are wonderful. And best of all - less than $11 each!
We had a ride last weekend at the Spring Creek Greenway just north of Houston, and some of the riders asked about it and ordered one for themselves. Beats spending over $100 trying to find a neck rest that may or may not fit your needs!