Raffael aka. supcha has built this MIDIbox SID:
The impressing thing: just have a look on supcha’s posting counter - he was able to build the whole thing without any help from our side. 
A lot of additional pictures can be found at his website:
hey tnx,
now i got my first post here too
think while building the SEQ V3 some more will follow…
cheers
ps: i like the sound when i connect or disco a bankstick
Excellent work supcha!
So I’m curious - did you have no troubles at all, or did you just find all your answers by searching?
of course i could get many answers here in the forum with just reading around.
also the doc is excellent !!!
at all i just fried two parts, a 7805 and a EEPROM for a Bankstick -> R.I.P.
core and sid modules worked at the first startup
lcd also
just some led’s were blinking at the wrong place.
cheers