A step up from the go-kart that we all built as kids (and some of us still do…), this vintage DIY six wheeler is a great father-son project for cruising around the neighborhood and out into the trails. Uses a transaxle automatic transmission to act as a clutch, transmission, and differential all in one unit. Controls and steering are tank-like, two levers control the two sides of wheels. Seems that the TAT is the hardest part to source, but some searching suggests that an 1970 beetle may have used this unit.
Scanned PDF instructions from the original writeup in Mechanix Illustrated (January 1970) are posted on Vintage Projects.com. Sadly, I don’t think the $5 plans offered in the article are still available.