I've only used the MB paste, but the way I do the sunroof is

a) with sunroof open wipe the chrome track clean, top and inner track with a rag

( every five years or so I'll clean the black plastic linkages, insulating parts, mating surfaces with a good quality plastic UV protectant )

b) with a small 1/4 - 1/2 inch wide stiff bristle brush apply a thin coat of grease along the inner opposing surfaces of the track, I also apply a thin layer on the top surface of the track - the surface facing out the open roof.

each track only takes a small dallop of grease- each side equal to a 1/4 teaspoon or slightly less.

since the sunroof paste is expensive and a container of the paste is enough to lubricate 5,000 sunroofs, you may try offering a few dollars to a tech at your local dealer for enough paste to do your car.

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