Recently bought a 99 E430 sport with a broken key. I may part it out or try to get it running. To make sure that I don't waste $$$ on programming the key alone and then finding out that it's not compatible w/ current EIS and ECM, should I get used parts from a different car and get it all done at the same time? Is the ignition lock programming also necessary/required? There are some used parts on ebay that may work but I'm unsure of total compatibility. Any resources to check? Thanks in advance...

Bill