Thanks to Geezer and Slow for the responses. I ended up removing the magazine safety and thought I'd relate my experience. I also have a question at the end for anyone who's quite familiar with MkII's and Mk III's.
Items used for this mod:
1 - bench grinder
1 - set of jewelers files
2 - M5 washers
1 - SAE10 washer
Snake oil lube
First I watched several youtube videos the detailed how to remove the part. It seemed pretty straight forward so gave it a try. Keep in mind I've never disassembled any firearm other than removing bolts, barrels, slides, ...etc.
Disassembly went smoothly up to the point of removing the hammer pivot pin. I tried to remove the hammer and bushing assembly without totally removing the hammer pivot as recommended but just as I had only about a millimeter more to pull, all resistance on the pin vanished and it popped right out. CRAP!! After a quick review, things didn't look too bad and it was actually very easy to replace the safety and slide lock lever. Ok, back in business (or so I thought. More about this shortly).
Next came the really time consuming phase. I had picked up several M5 and SAE 10 washers as recommend in a some videos. As expected I had to open up the M5 washers slightly which is where the jewelers files came in handy. Just a couple minutes effort was all that was needed for both M5 washers. This is where my experience differs from the video I was emulating. I could not use two M5 washers and one SAE 10 washer. There wasn't enough room in the frame. After some checking I settled on 1 of each. This seemed to work so I buttoned everything up and was about to try cycling the bolt when, OH CRAP!!, what's this little spring doing laying on the table.
Turns out it was the sear spring. At some point, probably when I accidently pulled the hammer pivot completely out, the sear pin just fell right out. After about 10 minutes looking for a good online exploded diagram of a Mk III it only took about another 5-10 minutes to get the sear re-installed. That actually wasn't nearly as bad I was expecting. So I buttoned everything back up a second time and tried cycling the bolt several times. Hmmm. There seemed to be a problem. The hammer wasn't being cocked. So I had to disassemble it once again.
After carefully checking the my previous handy work I determined that the SAE 10 washer was too big and was preventing the sear from locking up with the hammer. So out came the hammer and the two washers so I could try grinding down the 10. I used the bench grinder for this. However, by the time I had ground down the outside diameter of the 10 washer I was left with what was basically a hacked up M5 washer. So I pitched the 10 and worked over another M5 to use. I installed both M5's and buttoned everything back up. Now the pistol appears to work as expected with less effort being needed to pull the bolt and the trigger seems, while not lighter, to break more crisply.
Now for the question. While I was cleaning up I found a small piece of metal that appears to be the LockDetent Plunger. Below is a link to an online copy of the Mk III manual and the LDP is number 55 in the exploded diagram. I can't really see how this part goes into the main spring housing. Can anyone provide some insight? And no, I didn't find the spring that accompanies it.
http://www.scribd.com/doc/8413154/Ruger ... ion-Manual
So, there you have it. Total time was about 3 hours but with most of that being used to shape and modify the darned washers. I think though that I'm going to order a Mk II hammer and bushing so I can get rid of the washers. I figure each face of the washers just adds unnecessary friction to the internal workings. Fyi, I used the Snake Oil on the washers and hammer bushing to prevent the extra friction. I'll take it to the range, Rio Salado, on Friday or Saturday and will report my findings.
Now, I just need to figure out how to attach a picture of my III for a little eye candy for anyone interested.
Btw, thanks again to Slow and Geezer,