Here is a reboot of https://www.weasyl.com/~zmansstuff/submissions/1585248/sunset-diaper-check and the 1st digital remaster where the traditional drawing wasn't deleted. When it is "to peek" Marty Carrots might have used his diaper and Matt the Mysterious raccoon is checking it.
Note this is digitally remastered and Marty's complexion is blue rather than orange-yellow

In the 600 club revival this appears in rock and roll all nite