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I have an early P500. First time for coolant change.I did oil at the same time when the seat and covers are off. Much less hassle. I pulled off bottom hose where it clamps to steel tube to drain coolant. About straight down from where front edge of seat would be.When filling there is an air burp bolt on steel coolant elbow at top front of engine. Forward of seat belt latches. At front edge of center console plastic.Cant miss it. Pull bolt, fill radiator until coolant comes out of bolt hole.Much easier than elevating front end and not wondering if all the airs out. Hope this helps. You're welcome.