Booster to MC Rod Adjustment

[FY1Cuda]

I felt silly clicking the "New Topic" button because I'm sure this has been addressed a bunch of times.  Replacing an incorrect MC on my son's Challenger with the correct MC. The car has stock power discs in front.  The master, unlike the one I'm replacing, has a rubber part of the plunger sticking out about 1/8".  The original (incorrect) one had the metal plunger 1/8"recessed from the mating surface. When I push the MC's plunger in with my finger, it is relatively easy for a distance and then gets stiffer.  Do I adjust the rod for the TOTAL throw of the plunger? That is, should I adjust the rod length until it barely clears the plunger when the rubber plunger end is sticking out of the back of the MC (as shown in the photo)?

[Bullitt-]

 I'm no expert on the subject but I thought the rubber plunger was for manual brakes.. my '73s w/ power brakes do not use rubber plunger

similar question answered here about adjustment http://www.cuda-challenger.com/cc/index.php?topic=85566.msg855090#msg855090

[FY1Cuda]

Thanks.  I checked multiple sources and they all indicate I have the right master cylinder.  I set the rod distance to just miss the MC piston and put it in.  Hopefully, it works.

[Chryco Psycho]

the rubber O ring should not be in there & the pushrod should not move the piston when bolted up but should just touch it

[FY1Cuda]

Thanks, CP.  Took off the MC to take another look at it and remove the rubber gizmo at the end of the piston.  Turns out that the "rubber" thing is actually steel, so I left the booster rod adjustment very close but not depressing the MC piston and bolted it back up.