The cover is a standard item from aircraft suppliers. I've considered one for my plane, but I'm thinking about using a screen instead... it too will keep the bugs out, and since there's virtually no airflow into the tube it shouldn't affect anything.
My project today, and for the last few days, was to build a new tailwheel for my plane to replace the junky caster wheel that looked like it belonged on a supermarket cart. Commercial ones were all either out of stock, too heavy, and/or too expensive, so I designed my own. Definitely the most complex shape this noob has yet made, and a bit of a challenge on a mill/drill, but I'm pretty happy with how it came out:
View attachment 95596
View attachment 95597