I don't know? When the adapter is mounted on the scope eyepiece it has to be pulled out about 4 inched so it can see a 20 mm strip that is used to locate the chamber insert.
Hmmm, also wonder on the off set scope mount..If it would work for M1C and M1D garand... with their offset scope mounts...???
It sounds as though it needs a line of sight from the rear to the chamber ? If that's the case I'm not sure how it would be set up for use on something like a M1 / M1A which has a solid rear receiver.
It seems there's some moving parts that will have to re-position very accurately to be able to validate a scope hasn't shifted at all.