Decided to tackle my first oil change since purchasing the car (1995 S4S) last year (had my mechanic perform this task previously). Purchase the oil filter from JAE and oil from a local BMW dealership (10W60 which btw is more rare than a Sasquatch sighting). Read all the oil change and jacking instructions as per LEW,,,, - jacked up the car with stands in place - crawled under with my trusty 19mm wrench in hand and,,,,??????!!!!!! Lotus is using a drain bolt requiring an Allen key,,,not a run-of-the-mill 19mm bolt head. AARRGGHHH!!! Of course I do not own such an animal. My question(s) is/are: - what size Allen key should I be use to get the oil drain plug out with? Not much clearance due to a strut in the way. - any other surprises I should be aware of before proceeding? - the oil filter came with a small O-ring. What the heck is that for? - I am even considering purchasing one of those hand held pumps whereby you can extract the oil through the dipstick. Has anyone tried this method of oil change? Would be very convenient (no jacking, crawling under the car, or spilled oil on the floor). Thanks for your help!