Just so you know.....
I have experimented with many, many, different types of earplugs, as I have an endless supply of many different types where I work.
The ear plugs that are being used in the pics above are NO GOOD. Those type of ear plugs suck-up & retain water and swell to a large size and become very heavy and hard to cast.
I won't even use this type at work because the sweat from work makes the plugs swell and causes ear pain. The only foam plug that I have found that will not retain water are the basic yellow, Bubble Gum looking ones. All other foam ear plugs suck up and retain water.
Sorry Tom. I don't mean to dis on your fly. I just don't want to see you waste time on a fly that isn't going to perform well.
I tried to coat the ear plugs you used with Flex-Seal but that didn't work either. Only the yellow ones work.
If you're going to tie ear plug flies, I would only use the type in the pic below.....