Thanks Jim! The red stamped serial number is hard to see except for the last two numbers. Some one has handwritten the serial numbers in. It looks to me like 96189. The 189 is definite the 96 could be 9E. I did also find another number on the inside of the back. It is handwritten A236. I was also thinking it was refinished at some point. Most of the L-7 guitars I have seen from this time period have a sunburst top. Was a dark stained top available then? What would you recommend to clean it?
You are correct about the tailpiece it is a piece of black plastic mounted in the center. I have not been able to find another example, perhaps it could be home made?
I have not been able to try the DeArmond yet. The guitar did not come with the correct cable. Do you know where I could source an adapter or a cable with the correct screw on jack?
I will take some better pictures. The back has two cracks. One has been fixed the other will need to be fixed before winter.