I did mean 5/32", Tom, but when I was measuring things, I found that it's actually 3/16! My main spar's center is zactly 4" back from the LE, but when I go back to the 5" suggested, it is right-on! It's got a little hardwood tail-beefing and some hard points for wing bolts and dowls, but is mostly original!

Joe, I also have a Tow release, but mine's not operable in that I'm using a 4-channel. Mine is just about longitudinally and laterally centered in the upper surface of the wing. I could not see where your's is in the pix??, but it obviously does the trick ... neat pictures.

Thanks, gentlemen ...