Get yourself a set of John Calvert's Caltracks.
www.calvertracing.com and you won't have to worry about traction, but I would not lift the back end up. With that gearing you are kinda stuck with the size tire you have now and the RPM it is spinning. I run a 28 inch MT Sportsman on my 65 FB and a 28 inch tall slick at the track, but it is really close. As far as ET's, I would not be concerned about running to many times. Unless you have box welded the spring perches and back braced the rear end housing, and are running 31 spline axles in a 9 inch, if youre HP estimate is right, it will tear all that out on your 1st pass anyway. If you are not running hardened parts in that C4 it will also go by the wayside. Unless you are running a trannie shield, flexplate shield (or a JW Ultrabell) and all SFI parts, I would not risk losing my legs, untill all that was in place with a stock C4.
I'm not trying be negative, just want you to be safe..
Ron