I dont think that the ute diffs are any different, but I am sure Dodgeman will clarift that.
I am currently cutting down a skyline lsd for my 1k and the motor is a turboed a15. Its pretty much the best choice available. You could run with a smaller diff like the H165, but your gain would be minimal. For all the cost and effort, go with a Borg Warner. Common as muck, plenty of ratios available, and LSD.
Overkill, perhaps, but better to much and it never breaks, and to little and all that money wasted.
One thing to remember is that a diff is designed to handle touque, not Horsepower.
In theory your could run a blown 454 witha H145 and it would survive. As long as you were real gentle with the clutch release, and you never reved it much. I dont reccomend you try it, but it illustrates the point.
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well it will be set up for street and ocasionall race also i drive resonably hard
If you want to drop skids, race and for the street then overkill is the answer.
If its a sunday cruiser, then you could possibly get away with the H145.