Ship it to me so I can verify by close inspection if it is a Big John. From your pictures, I'm 90% convinced it is a Big John that has some customization with the two cockpits (instead of one), four ailerons vs. two, the airfoil sections look a little thicker, the fuselage shape around the landing gear and the gear setup. If you could post a picture of the tail, I can confirm. Span of the upper wing is 76 inches.

Here's a picture of mine to compare. It is from the Model Engineering of Norwalk kit of BJ the First with some OMT (One More time) features. BJ the First plans are available from Bill Northrop, OMT plans are available from RCM Plans.