Hey I am not sure if you are aware but Mudline Motorsports offers a free tech support line. I was having issues with my 2005 LTR450 concerning TDC last year and reached out to them, they walked me through how to identify the timing marks and it was a huge help. Here is a link to their website!
Dirt bike and ATV sales and service center. Dirt bike and ATV repair. Premium access to thousands of aftermarket parts. Located in Mountain Top, PA, 18707.mudlinemotorsports.com