ZZ Top: All New Hairy Situation on Tour

Just when you thought they couldn't get any hairier ... ZZ Top's Dusty Hill switched things up in the band by playing a new instrument, but keeping the band's signature look.

Dusty, who's still rehabbing a dislocated shoulder, had to trade his bass guitar for a keyboard during their summer tour and since ZZ Top's hardly the grand piano types -- he enlisted Jimmy Shine's Workshop to build 2 badass custom rigs.

Jimmy says he fitted hand-polished chrome tubes and trucker-style chrome exhaust guards to hide wires and mount LED lights ... then welded the gear to the keyboard.

For the second one, he attached white Nordic Alpaca fur to match the fuzzy guitars the band played in the video "Legs." Total cost for the hairy nostalgia -- just under $15k.