Dave you can use a ball peen hammer to "peen" the edges of the master link after it is assembled and accomplish the same thing as the press tool.
At about 260k miles I replaced the head gasket on my 95 E300 and while I had it apart I went ahead and replaced all the slides/guides. I just (within the past month) rolled in a new chain at 285k miles. It was still on the original chain
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