I didnt think keyless entry could be done on a vaccum lock type deal. Cool. I did one on a Honda Civic once, lights flash, remote start, that sort of deal. Plenty of wiring, to do. Should be easier on the benz though, less wiring. Find out where the locking system wires are first and then splice them.
I just bought and installed an Omega Research keyless unit on my daughter's BMW E30. Price--$21.95 Installation time--15 minutes. I did not set up any bells and whistles. The guy that runs the site on Ebay was very helpful and took the time in an email to me to explain what is needed for a W123. Basically,
a solenoid that costs an additional $25. If interested, go to Ebay and put "Omega Research" in the search engine. The guy's moniker is Mypushcart. Hope this helps.
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