A while back, I offered the tutorial in how to remove unsightly wording & nomenclature from your Replica Colt Navy.
Commonly known as Defarbing, here I will show the process I used on a Spiller & Burr...
one could remove the barrel and proceed, but the extra work is totally unnecessary.
You will have to modify your file
and you will find a small VACUUM SUCTION BASE Vise is helpful...I had mine , I think I got on Amazon, but Harbor Freight has some or Ebay.
The gun was prior tuned to solve a minor bolt fit issue common with Piettas.
The Black powder Only & <logo> F.LLI Pietta - Made in Italy are a glaring anachronism IMHO and had to go.
So first I cut the file ( an 8" Medium Mill ) to remove the tang , this allows you to use the file as a draw file length ways down the flat of the barrel ...
you will want to use blue painter tape to mask the other barrel flats & I also used it to close off the frame & action
after the first 2 or three stokes you will note the roll marks actually raised the metal a bit , in fact the letters are not very deep
Only maybe 30 strokes were necessary to completely remove Black Powder only .... F.LLI Pietta part is a bit deeper and that side took 36 strokes....
It is important to clear your file about every 3rd pass to remove fillings otherwise they act as little bearings and the file skips and does not cut well , also they can lead to scratches which will require more work to polish out.
I used 320 Wet Dry & 400 Wet Dry , you can use water ...I tried Moose milk because its mostly water and I had some in spray bottle... it worked just fine