John Quade played Augie Detweiller in 'Hazzard Connection'. As you said, he also made several movie appearances alongside Clint Eastwood, including Westerns 'The Outlaw Josey Wales' and 'High Plains Drifter', and he was Chola, the hapless leader of the Black Widows biker gang in 'Every Which Way But Loose' and 'Any Which Way You Can'. I posted a picture of him as Chola and Augie several years ago in the trivia thread.
Speaking of Clint Eastwood's co-stars from 'Any Which Way You Can', don't forget that his big fight rival Jack Wilson was played by William Smith who was Jason Steele in '10 Million Dollar Sheriff'.