House on Bare Mountain (1962)
If you know how to parse it correctly, the title tells you everything you need to know about this low-budget nudie flick. "Bare Mountain" refers to the mountaintop girls school/nudist colony that's the setting for the film; I suspect that "House" refers not only to an actual house there, but to House of Frankenstein and House of Dracula. The movie's about an old woman (actually Bob Cresse in drag) who runs the naked girls school as a cover for her moonshine operation. At some point, the operation is visited by Frankenstein, Dracula, and the Wolf Man.
There are conflicting reports on where the monsters come in. According to a review at Happyotter, the moonshine still is operated by the werewolf, but IMDB's short summary suggests that the monsters don't "invade" the school until later. Either way, the movie has a scene of the Universal-looking Monster spiking a punch bowl and that's awesome.
A couple of things about this movie are worth noting. First, as far as I can tell, it's the first movie in which the Monster has been misnamed "Frankenstein" in the credits. Mistaking the Creature for his creator is a much older phenomenon than that (in fact, Son of Frankenstein has Wolf von Frankenstein lamenting it early on), but the movies at least had gotten it straight up to this point. Even Hellzapoppin', as loose as that was.
The other thing has to do with the Monster's look. "Serious" remakes/sequels (even the extremely cheap ones) understood that they couldn't just steal Universal's design, but it's a different story with comedies. Maybe Universal wasn't that protective of its version in the '60s; maybe rules about parody apply. Either way, the popularity of the Universal version made it an easy short-hand so that audiences could immediately identify the Monster and laugh as he acted against type. Like spiking the punch bowl.
The Evil of Frankenstein (1964)
I skipped over The Revenge of Frankenstein (1958), Hammer's sequel to Curse of Frankenstein, because there's no real Monster in it. I mean, there sort of is, but not really. Not as its own, unique character. Maybe I should've included it anyway.
Either way, the third in Hammer's series was The Evil of Frankenstein, a narrative and stylistic departure from the first two. Though Peter Cushing again plays Baron Frankenstein, he plays him with a different personality and flashback scenes in Evil contradict events of the previous movies. Also, though it's supposed to be the same one from Curse, the Monster looks completely different. Thanks to a deal in which Universal agreed to distribute the film, the Monster's look in Evil was able to include some of the famous design, including the flat head.