Current Projects chat and miscellany

Bb shell (without spacers) measures just under 68mm. Can I just stick a modern hollowtech onto it without spacers?

Yes. It has had an MTB crank in there, they are designed for 73mm shells so there's a 2.5mm spacer per side if you use one in a 68mm shell.

Of course, if the frame was built to take MTB cranks, the chainring or spider of a 6600 might hit the chainstay, but you can cross that bridge when you come to it :)