TuckerBag from this forum has done it. The thread is here:
http://www.nsr250.net/forums/viewtopic.php?t=10640&sid=a002b59b3889e1a583e2f3be656a31f3
His Blog is here:
http://edetuckracing.blogspot.com/2011/07/mototassinari-reed-blocks.html