Need help identifying Martin XBTM-1 tail markings

Tools, Techniques, and Reference Materials Reference Materials
1

I’m having trouble figuring out the alphanumeric stenciling on the tail of the Martin XBTM-1 below. This is the clearest picture of the Martin XBTM-1 I could find. I have two of the three alphanumeric stencilings deciphered. The 3rd set has me stumped.

XBTM-1 then 85161 (or 85162) on the rudder since those were the only two numbers for the XBTM-1s
then below the XBTM-1 stencils ??? is where I’m stumped.

Any help much would be much obliged.

2

Fin - “NAVY” above “85162”

Rudder - “XBTM-1”

Steve Ginter’s Naval Fighters Number 24, Martin AM-1/1Q Mauler will be invaluable to you in this effort…

3

Thanks Turtle!

I figured there was a chance I had things goofed up. Thanks for the reference as well.