IMO the 30 series prolines are nice but they don't give the truck enough width. I have been most happy I think with the Traxxas 2.8" Annaconda Rear mounted tires for Jato:
http://www.amainhobbies.com/product_...ducts_id/19203
are the absolute best tire for parking lot and high speed running w/o ballooning. It's got a 4.25" measured diameter and can easily be geared for 45+ in the .5. Also the Jato wheel has a wider offset and widens the truck just right.
I'll post some pics as I work on it, but the mount will be pretty easy as there a RCM mount for the LS10 and I looked it up and the center diff mount is the same part no. for both.