Upper wing attach fittings

[John Gadzinski]

OK, maybe I'm slow here, but after studying the plans and combing through the builders manual, I'm having trouble picturing how the upper wing attaches to the cabane struts. I just joined the two halves of the wings together and am now looking to frame in the fuel tank. What I don't understand is how you would bolt something onto the wing spars if the insude of the spars in permantntly covered?
Help anyone?

 

[Skybolt540]

 

[Beej]