69 Barracuda 318, brake pedal sags

Wondering if the pedal is actually low or the switch needs to be adjusted. Take a look at the switch and see if you can adjust it a bit. The master cyl is what holds the pedal up, if its actually low you could be looking at a master issue or possibly the wrong rod from the pedal to the master. Also make sure the bolt that holds the rod to the pedal is tight and correct. Its a shouldered bolt. Did it do this before you did the work? Check the easy stuff first!