66 88 FFR - and it looks like the brake have never been touched, except by salt water. Slave cylinders rotted on their insides. ugh.

I'm trying to take things apart to degrease and wire brush, and give a coat of rustoleum for future protection.
I unboltedthe brake backing plate, and the front spindle assembly seems to be solidly attached to it.
I've soaked this baby in cleaning fluid for a few days, and it doesn't seem to want to separate from the backing plate.
Is it necessary to separate it in the first place? Or should I whale on it with a bigger mallet?

Many thanks