Is there a way to permanently disable or remove the locking mechanism from a S&W revolver without adverse effects?
...but forgive me for being paranoid. If you ever had to use it for self defense I think it could be legally risky to have used a "modified" handgun.
Removing a "safety device" is only a real issue if the shoot is not clean. You might have a PI attorney try to depict you as some sort of reckless monster for disabling it, but if the shoot is clean, the gun should be back in your hands before the plaintiff even has a chance to contact an attorney.
If the shooting is somehow painted as accidental, the fact you disabled the lock may be used against you.
Of course if you are in Austin, the PD will try to hold the gun indefinately and destroy it out from under you. Once the case is No-Billed, go to the PD and scream very loudly to get it back.