That is about what mine tonks along at (1850 ish is 100 ish but I sit a tad under) and it seems to be the sweet spot (33 inch tyres 3.9 diffs and 4L85 tranny).
When I put the 35's on it is def not as happy on the bitumen (runs a tad hotter and uses more fuel esp if the Van is attached).
But... mine is not a P400 and those Cobras' are pretty much a different critter entirely to the older 6.5's.