Currently, I’m building up my first MB-SID. Everything’s fine so far, BUT:
Did anyone bear in mind what to do with the (now) SID- and PSU-less C=64? Throwing away is not a choice.
'Cos I don’t want to use it for my (going to be) Synth, http://paulrickards.com/?p=910 is an option.
But I still have a '83 built motherboard with 6510 etc left behind…
Any ideas?
I sold my c64 remains on a lcal auction sites- made somebody happy!
I remember bidding on a C64 at eBay, pulling out a fine SID and sell the SID-less C64 for the same price. So basically I got a SID with some eBay work for free. You see a lot of C64 spare parts on eBay, that’s how ripped C64 end. Or someone puts a SwinSID in it and it’s good as new.
I once repaired a Flatscreen with Caps i scavenged from a SIDless C64. Despite their age, they worked until then, so i figured they were good for another few years.
The nice coloured ribbon cable of the keyboard can be reused for Diy or repair projects, too.
It’s a little sad, to pull such a great machine apart, but the ones i had were in bad shape anyway.
A SIDless C64 makes for a good testbed for testing SID chips later on, should you have any problems with the MBSID build. Also, you can install a http://www.swinkels.tvtom.pl/swinsid/ (swinsid) any time and enjoy some cool C64 games (Hawkeye for example :)).
Maybe you will build a new PSU for your MBSID at some point (higher efficiency, better protection circuits), then you have a fully working C64, which is invaluable 
Many greets and enjoy!
Peter