I have a listing I did 25 years ago - never updated:
House of Mystery 72,226
House of Secrets 95
Tales of the Unexpected 126
Kid Cowboy (Ziff Davis) 2
Gunfighters (Charlton 1979) 53
Top Secrets 5
Perfect Crime 2
Loco 1
Cracked 1-5,12
I've seen LOTS more in the interevening years. Just failed to list them on the cards. Don't recall any Treasure Chests, but that could easily be a memory problem. Hillman rings a faint bell.
I always thought Maneely pencilled and inked his own work. DocV can answer that better than I can. The variation in his style was attributed by me to the amount of time he had to invest for the amount of money he got in return. If he had to do ten pages to make $100, he did the very quickly. If he could do five and make the save $100, those pages were better drawn and more finished.
Peace, Jim (|:{>