Bill,
A few quick ideas which you probably have already considered. But, it's good to "air them out".

Like Burkard I would be weary of removing all of the sheeting. There is quite a bit of weight in that sheeting though. Eight pieces of 3/32 x 6 x 48 can get heavy, how much would you save with contest? I think I would adopt the Taurus type of covering. Glue in a sheet on the leading and trailing edges with cap strips on the ribs and consider shear webs. Reduce the span to 96".

Hollow out the top blocks even more or go with Cees's method and remove them. Hollow out the wing tips, stab tips. Cut lightening holes into the 1/8 fuse sides and take a bit more out of the fuse ply doubler. Though I have already laser cut quite a bit out of it and the wing ribs.

I wouldn't open up the 3/32 balsa fuse especially aft of the wing. There is a lot of moment there and plenty of force generated from that huge stab, could crack the the fuse if not trussed correctly. Anything forward of the firewall (cowl and such) is for looks. Obviously, no structural worth at all. Remove whatever you can there or thin it out. Finally, ribs one thru five are all ply or ply/balsa laminates. More than anything else just there to provide a safe, structural surrounding for the tube. Could experiment with reducing the weight with those 10 rib locations. Although, as I mentioned above, I have already cut lightening holes into them.

Hope this helps a little bit anyway. I'll study it a bit more.