The series is set is 1972, but the only time in the 1970s that Don Rickles and Sammy Davis, Jr were guests on the same episode of "The Tonight Show with Johnny Carson" was on 1 Oct 1970.
$9 in 1972 (when the series is set) is worth $54 in 2018.
The grey gothic church used in the pilot and several subsequent episodes was unavailable for shooting during this episode so Mike pulls up to a pink Spanish-style church in the scene where he is taking Eddie to confession.
This episode includes a clever parody of "How The Grinch Stole Christmas," including a rhyming narration reminiscent of Dr. Seuss and Frank and William singing a Whoville-style song as they happily do their yard work.