I tried it earlier this morning and the server couldn't be found. It's workin now though...
http://www.ww2mmrefphotos.com/photos/SchwimWalkaround.htm...and has some great pics of the MG mount down at the bottom. Here are a couple...
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There's also a site by David Williams. He does a great build of the Schwimmer, but he also has a detailed reference page and pics and drawings of various parts. Here's the beginning page, which is the reference section...
http://www.users.bigpond.net.au/langlotz/305%20projects/schwimmwagen1.htmHere's his MG mount details page...
http://www.users.bigpond.net.au/langlotz/305%20projects/schwimmwagen2.2.htm#mgpostOn it, you'll find lots of information as well as this great drawing he did...
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While I was looking around, I found this site which sells parts for Schwimmwagens and Kübelwagens. Just in case someone just happens to need a real MG mount, here's the site...
http://www.blitzbikes.com/id26.htm