Deranged (1974) is a goober version of Psycho, with Ezra the weird farm boy as the backwoods Norman Bates. (Both flicks were inspired by the Ed Gein case.)
Ezra's domineering mama dies, but not before warning the boy about wicked wimmen. And after about a year in the ground, Ez digs her up for company.
'Course, she smells a bit, so he bones up on his taxidermy and embalming. Eventually he collects a whole set of corpses, nicely arranged around the dining room table.
Which comes as a nasty surprise for Mary the barmaid.
This is a surprisingly good film, with some dark comedy and a fair bit of glop. We've got dead bodies galore; one newly dead body, upside down; one barmaid in her skivvies; one fat lady at a seance; deer hunters; girl stuck in bear trap; demonstration of proper corpse dressing. Two breasts, recently dead. The cheesy narration by the newspaper columnist with the bad necktie kinda seals the deal and makes Deranged a solid three-coiler.