OD trans behind a 273

In the grand scheme of things, its not that much work to chop, template and weld for the a500, it's if you want to do it. For the OP there may be some other issues narrowing his selection a bit, as others have said. Good luck on the research!

Here is a link that may help:

http://www.dippy.org/forum2/index.php?topic=231.0