Do take all necessary precautions while handling/cleaning animal waste/ mice pee/poop. You don't want the hantavirus.
As much as I love old Chevy trucks, frankly there's not much left to love with that one. Major mechanical parts, body panels, hired body work, hired mechanical work, all the small stuff, etc... add up over time. The best advice I ever heard as it relates to any old car/truck, collector vehicle... is buy the best example of what you want that you can afford. Dragging one home from the fencerow is kinda romantic, but usually takes too long and cost too much.
Of course I'm just some guy with a keyboard. It's your truck. Do what you want to do - but do it safely.