Brake Issue???

Ok so when I drive my bug around town ALL day long I never have any issues, BUT as soon as I get on the highway and drive at 65-70 or so, and get about 15-20 miles, the left rear brakes start to apply meaning they dont lock up but they start to slow the car and smoke (*smoke is bad) so then I have to pull over and get my trusty rusty screwdriver and back the adjuster off to free it up , after thinking it was the line collapsing, I changed it to a expensive german line and it still did it , then someone told me that it could be the adjustment locker something that keeps the adjustment things from moving???

Any thoughts on this and does anybody know where I can get this part to fix it?? when I get down to Fl Im gonna need to take the car on the highway alot more than I did in Ga and dont feel like stopping to mess with it

and yes I went a lil overboard with the smileys, But Im boared

I had the same problem on my old black 67. It actually caused my polished 5-spoke to heat up and melted the center cap and it fell off. I can't say what actually fixed it because I went through the entire brake system at that point.

I really like that flat black look, but up on the first pic the locker is exactly what I need!!!!!! I think it fell off when I lost my wheel going up the mountian