Before you break off any more fasteners, you need to acquire a couple of things.

1. A supply of KROIL www.kanolabs.com

2. A Propane torch

I like to buy KROIL by the gallon. It costs a lot less per ounce that way than in aerosol cans or quarts. If you store it in glass containers such as quart Mason jars, it won't creep through the seams of the metal can it's shipped in, and it lasts about 3 days past forever that way. A few ounces in a metal pump can oiler on the workbench will come in handy for all sorts of uses, and it's much better at breaking loose rusty parts than any other penetrating oil I've used in the past 50+ years. Warming up a fastener with the torch before applying any kind of penetrant is a good idea- - - -so is a liberal dose of patience- - - -penetrating oil needs hours, if not days to do its work. Have fun!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!