My advice, just leave it alone. Made it 46 years in solid original condition. Something I really enjoy doing on originals like this : while keeping her drivable all the time take a weekend here in there and restore each working component to as new. Carefully preserve- clean - renew all the original finishes and soft pieces. It's really a joy to drive something as it would've been back in the day with all the components working properly, engine in a perfect state of tune, column shift greased and adjusted properly, tight front end etc....By '72 these base trucks drive like a dream when everything is operating as it should. Your truck has great soul, if you're thinking about modifying it, just sell it, plenty of dime a dozen long beds to turn into anything you want........
Enjoy her, she's a good one!
Steve weim55 Colorado