For what its worth I wrote to world models asking about the CG on their 60 size zero. Their response was:

Dear Dion,


Thank you for your enquiry. The ideal C.G. position is 100mm (3.94 in)
behind the leading edge measured at where the wing meets the fuselage. In
order to obtain the C.G. specified, add weight to the fuselage or move the
battery position.


Guess what? Thats about 1 inch behind the spar on my plane. The wings should be pretty close in comparison. I took the heavy hub off my engine and mine seems to balance about 1/4" behind the spar right now. I think I'll go ahead leave it that way until its first flight (unfortunately we just got more snow last night here in Illinois). I'll probably finnally invest in a cg machine. I built a cg checker but it basically has dowl rods the plane rests on which works great for all my 25 size and smaller but my 40 size planes are a bit too heavy for it to work without imprinting the wood. Also I did get a chance to weigh mine tonight. With my .91 and all I mention in the previous post I weigh in at 7lbs 4oz. NO LEAD WEIGHT ADDED! I think i'll have to set my throttle travel to about half because this .91 four stroke pulls so hard it scares me. ha ha ha I love my thunder tiger .46 pros but they got nothing on this four stroke. Although to be fair I would have add a $100 bill to the nose of my .46's to balance it compared to this engine!