Correct, Rodgervich.
The removable recoil lug is a plate that is sandwiched between barrel shoulder and the receiver itself.
However, chamber measurement in rebarreling to fit an action is normally expressed as how far the cartridge case head (headspace gage) protrudes from the END of the barrel, and is not affected by the thickness of the recoil lug. This is assuming, of course, that you re-assemble your barrelled action using the exact same recoil lug originally removed from it.
In other words, measuring for the chamber reaming depth (to give correct headspace) is done exactly like that for Mauser actions.
Just don't go switching recoil lugs during your rebarrelling work!
HTH
John