This question was asked a few years ago and the answer, while very useful, is not resulting in a complete solve for me.
Here is the previous thread - Tightening bottom bracket prevents crank spindle from turning
I am having a very similar issue. I have 68mm shell and a cartridge BB that therefore requires a spacer on the drive side. With the spacer installed there is quite a lot of friction in the spindle when I tighten up the BB.
I know that I should be able to tighten both sides fully, so my question is - is a certain amount of friction expected or should the spindle spin totally freely. Any advice would be much appreciated.