Torque wrench use on hitch ball

[rtcassel]

The 1000/10000 pound Equal-i-zer hitch I bought uses a ball with a 1.25 inch diameter shaft. The tag on the ball states that it needs to be tightened to 415 lb-ft, and this tightness needs to be checked daily. Wrenches that will measure this amount of torque appear to cost at least $400 to 500. Is this sort of expense necessary? Looking at the size of the shaft and its nut, and the heft of the hitch head that it will be attached to, it appears to me that I could not possibly tighten it too tightly, with or without a torque wrench. That is, I am not going to get it any tighter with a torque wrench than without one. Is this thinking sound? How do you with similar hitches handle this situation? Thanks for any advice. Tim