you can also use truck bed coating. It comes brushable and also in a rattle can
I looked at several and have had a couple applied to truck I have owned but for the 3 Wheeler purposes this stuff sounds interesting.
https://www.durabakcompany.com/product/durabak-bed-liner-quart-smooth-2/It sort of seems like if one were to purchase a new 5 Speeder the first thing to do is at least undercoat the mudguards with stuff like this.
