With his rough speaking voice and often gruff manner, Willingham soon carved a niche in small supporting roles in "Sheila Levine Is Dead and Living in New York" (1975, as, appropriately, a school principal), "The Boys in Company C" (1977, as a sergeant), and "First Monday in October" (1981, as a Nebraska attorney). He was inactive in features for a time in the mid-1980s as TV work expanded. He had previously tried series like "The Texas Wheelers" (1974-75) and "When the Whistle Blow" (1980), and TV-movies including "Black Bart" (1975) and "The Gambler" (1980). Mid-80s small screen work included miniseries like "Dream West" (1986, as President James Polk) and telefilms like "Shooter" (1988).
The film role that gained Willingham increased attention and larger parts in the future came with a striking portrayal of the sympathetic general in "Good Morning, Vietnam" (1987). He has continued to play small parts which call on his Southwestern accent to add color, but he has also appeared in such high-profile fare as "City Slickers" (1991), "The Distinguished Gentleman" (1992), and "Ace Ventura: Pet Detective" (1994).