Try to find mirror take-offs from a Ford van upfitter who converts the vans to ambulances. That way the mirrors are already configured for the vans, and no modification required. Found mine on eBay.
Herb
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SMB-less as of 02/04/2012. Our savings account is richer, but our adventures are poorer.
I have been using MSN auto ratings to figure out what some of the differences are between years. If you type into a search "1994 Ford Econoline msn ratings" it will take you to the pages for that year and from there you can look at the specifications for each year and model, see a short overview of that year and any major changes they made, and search every other year that they have info for.