Remove master cylinder

[19challenger70]

Master Cylinder removal I have disconneced the push rod rom the pedal and removed the two nuts from the bolts what else am I missing?   

[JH27N0B]

2 nuts?  All the master cylinders back in that era had 4 mounting studs (manual) or 4 mounting holes (power).
Unless your car has a brake conversion with a newer 2 mounting hole flange master cylinder you need to remove 4 nuts.
I'm sure you have the brake lines off already too.  Other than that you should be ready to go, if you have all 4 nuts off, it should come off.  It could be rusted to the booster or firewall backing plate in which case a little penetrate oil, and a little banging on it with a mallet or prying should break it loose.

[19challenger70]

the backing plate has two nuts the master cylinder has four studs but I cant get the backing plate off the firewall to get to the studs.

[JH27N0B]

I've never worked with a manual brake Mopar, and the shop manual isn't clear on it, but I still am 99.9% sure there should be 4 nuts you need to remove, as the master cylinder has 4 mounting studs.  You may need to look around at the back of the firewall up under the dash but they should be hiding there somewhere.

[19challenger70]

I found them hidding.     

Thanks