Wanting to "upgrade" the sound & breathing on my '74 850 with the welded in peashooter mutes....pretty tiny openings really. I just scored some really sweet non-balance pipe original headers ($20 cdn!!!). Since my peashooters are not in great condition (scraps, dings, scars etc), I'm thinking I could try grinding/hole-sawing out the mutes to hear how they sound. Any problem with trying that (not sure if any internal baffle/mesh mounts up inside that area)? If I like the new sound/breathing, would likely split for nicer looking cans at a later date.