Thanks David - good advice. I will certainly re-apply heat to re-wet the joints. I'm also going to try contact cleaner to see if it's just a grunge layer that's adding to the trouble. It looks like the hole-through quality is pretty good, and I reckon that it won't be much trouble to remove the socket without damaging them. There are no sensitive LSI's on the board - not even any TTL, it's purely for electrical connections.
I'll try it this arvo.
