I am trying to do the same thing on my 86 420SEL. So far, the only thing I've seen is a kit from bergwerks.com. On my Jeep Cherokee, I had a long range Viper alarm with remote start that I loved. That would be my preference, or something similiar, but I don't know how realistic that is with vacuum locks. I had considered replacing, somehow, the vacuum locks with motorized ones. Not sure how that would work...