The rules state that you must have un-altered VIN numbers BUT... There is an exception for such bikes as yours and mine.
I bought my Buell from the the factory Race Director @ Buell. This bike was a factory "buy back" bike that I purchased and my VIN numbers have been all X'd out and replaced with "For race use only" stamped on the frame and engine.
Since the bike does not have VIN numbers per say, it is an un titleable bike.
However... I have the purchase slip from Buell (the actual pink slip) with the original VIN number for record. I keep a copy of this document with me at all times in the race trailer so I can provide it upon request. (which however no one has ever asked to see)
All tho... when you fill out your contigency form for Tech inspection, it will ask you to provide the VIN number to the bike in which you are racing. In this space I will usually put "Race Bike #1"
Here is the link to the CCS on line rule book... http://www.formulausa.com/forms
Thant about it. I hope this help's out. Mark!