I reckon you'll go close too...you'll certainly get him at the start..so practise your standing starts and even take it to the Creek for some runs against other cars similar to the one youre running. Tell him in the meantime that if you had the money to spend on your ute that he spent on his XR6, then you wouldbeat him in every aspect with the Datto, including looks!!
I watched a race at the old Seven Hills round about between a 1200 Ute and a R33 GTS-T Skyline and the ute got him at the start, but the Skyline was slowly getting it back after 100m. By the way I would never endorse street racing, try and get him to race you at the creek when youre ready. You mentioned that your engine is being built by Jeff Taylor,,,youre definately in good hands there, and Johns suspesion geometry will help get the power to the ground.