Removing glue from bricks

We just purchased a mid century modern home that has a lot of the same features as an Eichler but is probably a knock off. While removing the tacky sheet rock someone put up around the fireplace we discoved the entire wall is wall to wall, floor to ceiling brick around the fireplace. We have taken down all the sheet rock and we are now left with large globs of glue. We have started taking a heat gun to the globs to soften and scrape off most of the glue but we are still left with circles of glue that cannot be scraped off. Anyone know how, or even if it is possible, to remove the glue and bring the bricks back to new? They were in excellent shape so not sure why someone would cover them up, but then again they also covered up the wood on all the walls which was also in excellent shape. Any suggestions would be appreciated!