Bought a top only guide recently however no instructions on how to fit. A quick internet search has indicated I need to remove a spacer from the drive side. However, should the guide be up tight against the frame or between a spacer and bb shell?

If you’ve got two spacers on the drive side (68mm BB) then I’d remove the outer one (replace with guide) and leave the inner (against the frame).

The guide was presumably designed to work with both 68mm and 73mm BBs. A 73mm BB would only have one spacer.

As above – but you may find yourself swapping around to get it to line up neater

Thanks for your help, will go with ecky-thumps suggestion