Make sure you have removed all of the bolts and screws first including the rubber block on the inside ridge which buffers the hood. Remove the reveal panel in the wheel well, there are 3? 10mm head screws in there, the left side (drivers) is a ***** because there is a vacuum resivoir mounted in there, to un-bolt that, the nuts are inside the car behind the hood release, behind the tar felt layer.
You'll need to remove the long chrome trim on the rocker, under it are 2 #3 screws holding the lower "ear" of the fender. Don't be suprized if you find all kinds of rust there... Replace the screws with stainless ones.
Using a torch ( I use a cutting torch with a fine tip) heat the inside seam, using care because the filler is flamable. Now quickly run a carpet knife (sturdy old-style) in the crotch of that seam. Continue with the heat and cuts until you can tug on the fender with upward force to have it come free....

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Over 21 years I owned several:
w108
w110
w111
w115
w116
w123
w124
w126
w212