Over the years I have become an advocate of “leave the alone” but it’s your gun. If you have them opened I suggest as other have you leave the left barrel a little in the tight side.
Years have also taught me there is only one place to send a gun for choke work and that is to Jim Eyster in OH (
http://www.jimeyster.com/). Note I said gun, not barrels. There is a lot more to having chokes opened than running a reamer through them. First thing Eyster does is determining POI (not pattern) because not all chokes we’re bored properly (asymmetrically) in the first place. Eyster can correct that when he opens the chokes.
Any place that only needs to barrels today open chokes isn’t taking into consideration where the barrels are putting the payload in the first place.