Brake Bleeding
It's pretty simple ,
You connect everything up then slowly fill the resivoir , I like to gently push the brake pedal whilst peering in the open resivoir , just barley tapping the push rod -each time you tap it , tiny bubbles will come out the by pass port , keep doing this until they stop and you've " Bench Bled " the master without making any mess .
Always begin bleeing at the furthest cylinder from the master , this will usually be the right rear but maybe the left rear on your rig .
Connect a rubber hose to the bleeder nipple and stick it into a clear glass container (beer or soda bottle) so it touches the bottom .
Consider using " Speedy Bleeder " bleeding nipples , they're factory fitted to mist of those 90's vintage Chevy Police Cars cluttering up the self-service Junkyards these days , proper GM threads and everything .
ALWAYS use a box end ,
6 point wrench on the bleeders !!

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If they're rusty and don't want to open , get a 32 Oz. ballpein hammer and hit them straight on , the shock will break them so you can open them .
If you snap it off , A. you didn't hit it straight on and B. it was junk anyway so don't be too upset .
I hope this is helpful .