Just the one on the back of the mastercylinder.
I will be removing my power booster and going manual brakes shortly too.
Will I need to modify the firewall mounting bracket?
I saw a post once on plates for different applications and I'm pretty sure the hole positions for power V manual are different.Good question. I don't know if the plates are different. I don't recall anyone looking for one or the other so they might be the same?

I found sticky - http://www.forbbodiesonly.com/mopar...ting-plates-manual-vs-power-1962-1974.117312/
Plates are different, so looks like I will modify mine.
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