i once saw a mechanical kit that allowed 78-87 elcaminos to adjust tailgate position from a switch inside so it acted more as a spoiler at high speeds than a brick in the wind.. anyone else see this or am i imagining i did?
I would think that would be pretty simple to do. Use a power ram, you could attach it to the bottom, two could be needed, and put the button inside the cab somewhere. You'd have to modify the release lever or automate it or just remove it from the tailgate.
You could also put a hard topper over the bed and elemaninate the issue altogether. Lauren Engineering's packages are designed to help the El Camino be more aero dynamic and have less lift at high speeds. They make a spoiler for the topper to give more downforce to the rear end. I read an Article in Truckin' mag three or four years ago on Lauren Engineering's whole set up on an El Camino and they gave impressive numbers on the corse they were running after the installation.