That is a thing of beauty Steve
I am in the process of putting together a homage to the 6" Unitron model of refractor which Unipol is restoring. Mine is based around an f17.5 D&G lens and weighs enough that I have put a Ute crane in my back yard so I can get it mounted. Even though 6" f17.5 is some way from the Sedgwick achromat limit it doesn't have that much colour. I am struggling to get it to track properly (when viewing the zenith the dew shield is nearly three meters off the ground) but still managed to snap the attached
Cheers and happy friday
Jon