Nice find. You should be able to dissassemble them and polish them up.
Check out this guys work. https://mutantmics.com/
Restored, modded and hot rodded.
Ron
Dually options. For heavy trucks. Not sure if they will affect wheel balance on a pickup.
http://www.dualdynamics.com/products/cross-fire/
http://www.dualdynamics.com/products/valve-extenders/
I don't know where you live hemipower but this is for sale in central Ohio. May be the same one Diesel Crawler has. I am not sure what the model number is though.
http://columbus.craigslist.org/tls/1589595587.html
Ron