Any decent shop with a bottom bracket chasing'n'facing set should be able to do it, although whether they'd trust themselves to do it properly is another matter. The 68mm/70mm thing isn't an issue - just fit a 1mm spacer on each side of the BB shell once it's retapped.
Any decent shop with a bottom bracket chasing'n'facing set should be able to do it, although whether they'd trust themselves to do it properly is another matter. The 68mm/70mm thing isn't an issue - just fit a 1mm spacer on each side of the BB shell once it's retapped.