OK ..... well, here are a coupla pics within which I have tried to retain a bit of surface detail .. without making pics too huge. One pic from each side. Doesn't show enough but might help.
Now then ...... this gun was originally in pretty bad shape ... surface rust .... marks, dings ... far from good... even small pitting spots in places.
I elected to go the ''coarse'' route! By this I mean ... after a total strip down . I used a rotary wire wheel (fine) to totally remove all rust . This meant being quite tough on some parts ... but, I did attempt to keep the direction of work in line with already existing longitudinal lines/scratches . on barrel in particular. Cylinder in fact was not too bad...... so minimal wire work on that. The addition of marks thru wire wheel use was.... you may be surprised ..... minimal .. but then the bristles were way softer than the gun steel.
Short of ''pickling'' to remove rust this physical method seemed best ... altho sounding pretty drastic to most I guess.
It was quite successful ... and for the most part .. parts were taken back to ''self-finish'' ... steel!! Next stage was with finest wire wool .... and a lot of elbow grease . working on more stubborn areas and using non greasy cleaners like ''409'' .. to avoid impregnating metal pores with any oil.
Finally, in a few selected spots ..... usually small .. I used some 600 grit emery paper stuck onto small pieces of hardwood, toothpicks ... whatever worked .. and attempted to get these smoothed.
So ....... we finished with an all steel finish gun for the most part ..... complete still with some low spots and scratches from its past. This was fair enough for me and I then proceeded to do cold blue. All parts were rigorously de greased ...... initially alcohol bath but finally acetone. After that ... NO handling with skin contact ... either surgical gloves and/or ... pieces held by wire etc.
I blued using mostly 44/40 (didn't have Oxpho at that time) ...... and applied it fast and generously with cotton wool swabs ... followed on each piece by a water rinse and then very gentle buffing with finest wire wool. This removes some of already applied coating but prep's it for next application. And so on ... apply, rinse, buff - and repeat .... a good many times...... until the luster was about as good as it seemed to want to go.
Now I could have taken more care .... true, but this was enough for what I wanted ..... basically a piece that was once more looking as it should, complete with age and battle scares! Authentic if you like.
I got a new locking lever spring and mainspring thru Numrich ... these were missing or bust. And there it is ... far from perfect but ...... I was pleased. There is one patch on left side of barrel, that for no reason I could explain .... just refused to take the depth of blue of the rest! So finish is not consistent all over ...... the look tho is acceptable.
The bore was/is surprisingly good i am pleased to say - as were cyl chambers and throats. I keep it well protected in the safe with a good coat of wipe from my CLP rag or RIG.
This is hardly a definitive approach - and some may shudder ... but hey .. it's still a fine piece and way, way better than it once was. It now has a wee bit of holster wear too.
Hope this proves of some interest to you anyways.
Oh and .. I load Fiocchi brass using some 230 grn lead RN . same as I'd use for .45 acp but size em a tad larger.
I forgot to add ....... you mentioned proof marks etc ..... well, all original stampings are still as they were .... on left of top strap is ''MkVI'' stamped and cyl has its proof stamps over each chamber. i doubt if these would ever need to be removed or suffer, in process of this restore job.
And finally .... I did too in a few places try odd wipes of other blues ...... one was (forget make) a paste type . seemed to help in some spots. These were all selenium based cold blues IIRC.