runnig lean as f...

my T/A reads lean on my air fuel ratio gauge, i already test the injectors clean them and change the fuel filter what should i check next???

Well, if this is a stock engine...check the O2 sensor to start, then fuel pressure regulator, pump and finally...you may have a partially plugged injector on the left bank.

actually is not complete stock it has long tubes and a cam but the car was running great a few weeks ago then it started misfiring and doing $hit but i think ill go with the fuel pump cuz it doesn't gives any codes

MAF or speed density?

Check for exhaust leaks at the header flanges where the tubes are welded in especially. If there is a leak there it can/will suck in air and throw the O2 sensor out of whack.

1994 LT1...should be MAF.