How tight should the cups be screwed in. The instructions give the impression that it should be fairly tight & in my mind thats what I would assume. However, because the spacers are nylon & you need 2 of them on one side when installing into a 68mm frame they fold up within each other under very little pressure.

use your old spacers, hope ones are made off cheese!

Thats what I did in the end.. this is more of a post mortem

Use the same torque as Shimano quote, Park Tools website has instructions on fitting and how to torque the BB up using the unique spanner that fits the cups