Just changed mine in my P500 2 days ago. For the 500 the filter is stamped on each metal cap end which side goes to which engine part. Spring goes in first, then the end of the filter with the rubber seal in the middle goes to the filter cover side - seal goes around nipple in cover to seal oil flow through the cover to the oil passage towards the front of the engine.
Also as HondaSxS pointed out- you do not need to drain your oil to remove the filter, just put a clean drain pan under the engine - lined up with the filter housing and catch the oil that comes out. After you check the filter and re-install it, dump that oil in the clean pan back into the oil fill hole. Or, use the oil in the pan to judge how much new oil to add back in to bring the level back where it should be.