Shamelessly stolen from WG..
http://wildguzzi.com/forum/index.php?topic=87377.0
The UJ's should sit in the same plane - so if you look at drive shaft end to end, UJ surfaces are parallel.
I'd post a pic but I dunno how anymore (does the pic have to be already on line?)
Does this help? (Driveshaft w UJ either end viewed from above) >
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