You are correct, Mine just turned out that way ( 1.5 degress) but anywhere in that range will do. Like I said, if you build to the plans and install those brass tubes that hold the cabane struts and you place the tubes on the proper bulkheads just as in the plans you will come out O.K.
I placed my incidence meter on the center section of wing and after making sure that the fuse was level it showed 1.5 negitive, however if you turn the meter around and look at it from the othe side it shows positive. That is because of the way the scale is marked, one side + the other - I messured mine looking at the fuse with the tail on my left or the starboard side of fuse if you were sitting in the plane. If you look at one of the posted photos you may see the meter on the center section.

Steve