I have removed the "flag" part of the IL. Is it ok to leave in the key part of the locking system? Thanks Mac

I'd be concerned about the cam and tiny springs falling into the mechanism once the flag is removed. If you grind off the pin, there's nothing to hold the flag in place. The safest method is to remove all the pieces and plug the hole for appearance.

I took mine out too. It looked like the spring was on the end of a little flat piece that slid in small slots milled in the frame. Then that pushes against the cam that is turned by the key. After studying it a while I convinced myself that it was completely secure. I'm not sure how it could fall out given that the flat piece rides in slots cut in the frame. But now I really don't know.

If you plug it, you're going to have to secure the plug some way.

Not being argumentative here, but I think you can leave the "wart" alone as long as you do not remove the spring and keeper that holds it in. The keeper is shaped like a yoke and fits over the cam (wart). You really have to work at it to get that little spring and yoke out of there anyway. Just my opinion. As long as you get the flag and that little rinky-dinky toy spring out that is suppose to hold the flag down....but doesn't.....you should be okay.

There is a you-tube video floating about somewhere that details this and this guy only removes the flag and rinky-dinky spring.

I have a Aussie cop-trade-in 66-7. The Aussies deactivated the lock. The flag still goes up and down when you turn the key, but the little nub that actually locks the action was removed (ground off?).

I have heard of Bubba doing that also. Makes no since at all to simply destroy a part you may have to purchase if you ever had to send it home. AND....to the person that is not savvy about the lock and doesn't realize it has been disabled, he/she may actually think it's locked just because the flag says so.

I have removed the locks on all of my M638's and replaced them with the "Plug". The plug fills the larger hole in the frame and is held in by a spring clip. Note the middle gun.

Thank you for all your responses! I think I'll leave the key lock part of the IL system in the gun. The only concern was in my MP 340 that I carry for SD.
I am not going to mess around with the 617 and 627PC that I use for Steel Challenge. I have not had any issues with them so far. Thanks Mac

Being a belt ans suspenders guy and wanting to leave nothing to chance, I just take out ALL the lock parts, and leave the hole open.
This makes it just like the prelock guns, except for the hole.

I use the hole to my advantage as well. Every so often, I take off the grips and squirt some good aerosol gun cleaner into the action, including the hole. Shake it dry and then add a little Prolix for lubricant.

If I ever need to put the lock parts back in I have them, unmodified.

I certainly don't think removing the flag and spring and leaving the bolt in place will hurt a thing, or fall out into the gun. Nor do I see any problem with gutting it and leaving the hole open. I have done that on the IL's I have owned and just did not bother with the plug. If you are worried about the bolt parts falling into the gun....the plug is retained by a clip, so...there is something else you may be concerned about falling off. I think leaving the hole open makes sense and you know all you have there is a solid piece of frame with nothing to work loose and fall in the gun. I don't really think that would fall off either, but the plug can be noticed just like the wart can. Some folks find it attractive. I don't bash the plug users, but I'd just as soon not have the curtain over the window. People that know the difference will know it's an IL anyway. You can cover-up a mole on your face with a band-aid then....people notice the band-aid.