Going to resurrect this thread.
I've just installed a grandpa intake, 15 bing, and hi flow metal air filter on my e50 maxi. The air filter tube is pressed up against the frame a bit - even more so if I put on side bars. Looking at roffmans's setup it looks the same, but I can't tell for sure with the cover on. And Adrian did the whole copper tube for the same reason. Do most of you just leave the filter pressed up against the frame?