I recently discovered my March 1978 'American Classic' 1377 when moving some boxes around under the house and set it aside to have a play. It isn't holding air and a quick disassemble showed the transfer port seal is knackered so I'm going to have a look around for some nylon tubing that I can cut to fit. I was amazed at the amount of information there is on the web on how the 1377 has been modified but most of it seems to relate to the later phase models. I'm going to enjoy looking into what mods I can do on my gun.