The Federal Enclave Doctrine is a fascinating topic! Typically arises with jurisdiction authority questions rather than procurement related questions. Almost all military installations within the United States are Federal Enclaves. Unfortunately, I could not find a definitive list published by the Department of Justice or Bureau of Land Management to confirm that Ft Irwin and West Point are in fact federal enclaves... but I'm about 99% sure they are. That said, you should contact those installations to confirm (recommend either their legal office or the installation Historian office).
The impact a federal enclave has on a contract price adjustment is typically almost mute as most Federal Installations allow state and local laws to be applicable on the installation. There are of course major exceptions (e.g. states and municipalities where marijuana is legal). Additionally, the Federal Acquisition (and agency supplements) Provisions and Clauses are written in a way to avoid those nuances. When the issue does arise; there is volumes of case law which guide the decision making process. That is a long winded way of saying; you should seek advice of your contracts attorney.