hi mate.
i recently bought my 96 EL54 paseo, and the previous owner sold the door handle. so i bought one from a paseo being broken for spares.
i think the best way is to take the doorcard (interior panel) off, and then i think (not posotive) there are two nuts holding it in place so it doesnt fall. so i would un-do them first before you rip through the metal work (but that would take some strength)
then you have to pull the little metal door pully from the orange plastic/rubber fixture.
then get the new door handle, clip the door pully into the orange peice and then slide it into the holes where the screw parts are. then do the nuts back up on the back and you have a new door handle fitted