master cylinder brake booster plug stuck

[lucky guy]

I'm putting a master cylinder piston kit in my 03 4R. I've removed the snap ring that holds the brake booster plug and piston in, but I can't pull the brake booster plug out. It moves 1/8 or a bit more and stops. Might be an o-ring in the snap ring groove? idk, but thought I'd ask if anyone has any experience with this before I tried a puller on it.

Thanks.

 

[4Reak Show]

Never done a rebuild but just totally guessing, what about a dash of compressed in through the reservoir hole? I mean like a little bit. Might want to point the master cylinder vertical resting on a bench to not lose parts if they shoot out?