Dana 60 - Pinion depth problem

I think i found my problem, after talking to Yukon and reading your reply i removed the ring gear to locate the part number on the locker. While the person i bought it from stated it was for 4:10 and lower the locker is actually for 4:56 and higher. Since i purchased it several months ago i'm stuck. So my son and I are running the numbers to determine the impact if we install 4:56. The car is a little street and track. Since the quarter panels will be replaced we may opt for larger dia wheels, we have already mini-tub and moved the leafs inwards. Also have caltracs. So the hole shots may be great but top end will suffer. It's my sons first engine, est about 325hp. Hes only 15 so lots of time to think about a bigger engine. At least the rear will be ready.

Thanks to all that replied. You know i looked at gears, installed them, removed them, measured everything and looked for the obvious. Had others look at it, the numbers etc.. i was too close to it all. BIG THANKS!