what is this

Looks like the check valve from the AIR (smog pump) system. Is there one on each side?

the rubber gromet goes in da fire wall it looks like a vacume this might sound dum but is the vacume go to the brake light swith thing

Into the firewall? I'm lost then. Now that you mention brakes, it does look like the brake booster vacuum line - but it should run from the back of the carb, tbi, or intake to the brake booster, not into the firewall.

Aha! The missing link! That looks the hose that connects to the black mystery switch on the brake pedal assy. It goes to the cruise control doesnt it?

k so i dnt need it

Yes it does.

That is the vacuum line for the cruise control, should be taped up with the cruise control modules' wires as well. If you don't need cruise control, remove it.