Looks like a piece of cake, except it assumes that the frequency error remains consistent across the speed range. Probably a pretty good assumption and if its not and you set it so its spot on at X MPH you probably wont notice an error at X +- Y anyway
Still, its basically a track day in cost...
-Michael
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Michael 
'82 Euro SC 'Track Rat' 22/29 Hollows, 22/22 Tarrets, Full ERPB F/R, Rennline Tri Brace, Glass bumpers, Pro 2000's, 5 pts, blah blah blah
'13 Cayenne GTS