Bounty Hunter 4: Blood Mountain by Tiny Boyles and Hank Nuwer

Bounty Hunter 4
Blood Mountain
by Tiny Boyles and Hank Nuwer 
1982 Playboy

Loveable dirtbags Tiny and company chase after a computer genius and his stolen bank money, running into an Italian cult/terrorist group for their troubles. They pick up a lady bounty hunter along the way, and there's more action this time, involving mowing down ultralights with a machine gun.

The series coasts on charm over plot or action, but there's plenty of charisma to keep it going.

Paperback from Amazon