li'l mixer 1970
li'l gasser 1969
li'l yeller 1970
the fourth one you are thinking of is the li'l cashbox 1969, all of these cars were designed by John Bogosain who also designed the koo koo kar 1972, the flameout 1972, and the depth charger 1972, he also designed the royal rail 1972, the li'l gypsy wagon 1972, and the hemi howler 1972, and the der beetle bus 1971, the lug bug 1971, and the der volks van 1971, and the li'l stogie 1971, the li'l romin chariot 1971, and the li'l hot dogger 1971