That is awesome and very funny because I was looking at my old Aquaclear, and thinking about doing the EXACT (I mean the EXACT) same thing with it. We are on the same wavelength
The only think that held me back, was a) I wasn't positive it would work, and b) I couldn't find the downtube and was going to pick one up at the LFS this weekend.
You must tell me how it worked out (before I buy the downtube if possible

)
CMonroe...