If you dont have the tools or the know how ,go to B&Q get a piece of MDF the same size as the cabinet drill the holes for the bolts through the MDF and use the MDF as a spacer for the skirting saves any cutting leaving it intact in case you move home or move the cabinet .
Skirting sizes are usual 18 to 20 mm thats 3/4" to 7/8" in old money.
The Police won't have any problems with that, what they are looking for is you haven't got any gaps, that someone can get a bar in behind to leaver it off the wall .
Use the word KISS keep it simple stupid .
The more complicated a thing is the more likely they will have a second look.