Here is a link to what I think is the Dodge saginaw box. Looks like a very nice conversion. It fits much closer to the frame than the typical saginaw conversion. I did one years ago where I made my own conversion plate. I actually cut into the frame and installed a bent plate to get the box closer to the frame. This was on a one ton duelly, there was tire rubbing on the box .
Link to Dodge box.
http://rides.webshots.com/photo/1484219366080251109huOecf I suspect the reason CPP has not made the Toyota conversion for the AD truck is they just haven't got to it yet. Here is a link to a home fabricated Toyota conversion.
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http://www.hotrodders.com/forum/journal.php?action=view&journalid=2439&page=1&reverse=1
