I have had new wp bad on my ford vans, had a wp that would not fit right on my 03 MINI, was a cover if sorts and the mounting hole did not match. My wifes 2011 MINI S Countryman has a nightmare wp like the BMW, I relaced then the trans cooler leaked, then the dealer changed wp and trans cooler on warranty. Did not want to go to dealer, don't trust them, but they had the parts ( which means, happens aa lot) Might try glue on the oring before mating wp to block, always a chance it might slip down. Remember the old thermostats that were vertical and had to be stuck on with gasket sealer so they wouln't drop down.