I have a 1983 300SD and my alternator has gone bad. I have read few posts that mention an upgrade to Bosch AL129X from the stock AL117X. I have shopped this part from a few online stores, but, it does not seem to come with a pully. Can I use the one off of the AL117X? Also, I am a bit unsure about the rewiring of the wiring harness to the new alternator. Any help would be great.