Rock Halter
You know, like the halter tops wimmen wear. The ad would feature some gals wearing their halters, holding a shock wearing it's halter.
Foreskins
'cause that's what it looks like.
Seal Savers
I'm guessing that's what you are trying to keep the crud out for.
Tatoos
Color the cloth with simulated tatoos. Even custom make them to match photos of the truck owner's own tatoo.
Shock Mittens
It's different at least. Think of the nose mitten, then you get the idea.
Turtlenecks
Put a collar on it at the top with a velcro put-tight and it will look like a turtle neck
Dickies
Like a turtle neck, back in the '70's a dickie was worn with a wide lapel shirt or with a neru jacket. Remember Neru jackets and shirts? Ha!!
Bloomers
Kinda reminds me of the old fashioned wimmens under garments. Again, great opportunity for provocative ads.
Skirts
Another advertizement opportunity.
All suggestions can be worded with Shock or Rock in front of it for my suggestions as well.