Hi ozscott. Welcome to Coffee Snobs. It is a great place for learning and sharing your experiences! ;)
Im just going to comment on the Silvia and DeLongi/Solis grinder setup, even though Im a relative newcomer to the Silvia having just recently purchased one.
I couldnt honestly say that I would be finding the grinder a suitable match for the Silvia. As it was we were on the very last setting for our humble Sunbeam EM4800 and with fresh coffee it was okay but if it was starting to get on, forget it, the water would run through everytime (as opposed to that magical slow pour!) Even with the modification that you have done, I would still not be confident that youd get the grind needed for what is essentially a commercial group on a domestic machine.
We still have our old Delongi grinder, but it has been set aside along with the Sunbeam, replaced by the handsome set up of Rancilio Silvia, Rocky and Inox tray... ;) :)