expunged from 1972

Recently I submitted a request for a firearm permit in the state of Pennsylvania. I moved to PA from New Jersey in 1975 and have lived here ever since. The request for a firearm permit came back as denied. I followed the challenge process to find out why the request was denied. I came to find that what had been expunged from a 1972 arrest was showing up. The charge back then was a breaking and entering/larceny. The only trouble I have ever been in. I'm not so concerned about having a firearm permit but more concerned about this showing up on my record. I had submitted a request myself for a background check. Nothing came up, it was clean. To prove out my research I did a background check on some other people I know using the various databases available. The research on them came back with their criminal record. Their records showed up but mine was clean. My main concern is this. I plan on retiring from an organization I have been with for 20 plus years. I have a pension and a 401K I've been add to for some time. My plan was once I retired, I would look for another job that would be less stressful and better hours, maybe part time. Plus the current organization I work for is a worldwide company, 500,000 plus employees. They ran a background check on me in order to get the job. If this is still on my record and was expunged in the state of New Jersey, why is this still showing up on my records when they run a check for a firearm but I don't seem to see this when I had run a background check? Will this show up when I apply for another job?