Shortening the flushing hose
Clamp the clamping bushes 27×3.3 (106901PA253) firmly with pliers (preferably locking pliers).
Twist the hose nipple (106901PA251) loose with an appropriately sized spanner or suitable pliers. The flexible section has now been removed from the flushing hose.
Remove the clamping bush (106901PA253) with locking pliers.
Shorten the flushing hose (106901BP315, 106901BP400, 106901BP500) using a hose & tubing cutter, a sharp Stanley knife or a saw.
Use a knife to remove any roughness from the inside edge of the flushing hose that was caused by cutting or sawing. Smooth the outside with a file.
Clean the hose nipple (106901PA251) before fitting it again.