Trailer Reciever question

[GOPAPA]

I will going to pull a 6x12 U-haul trailer next month over 1000 miles and was wondering if anyone knows what the down set in inches I will need for a reciever to pull this trailer..

I stopped at the u-haul place and all the trailers are just sitting with the tounges on the ground . I could take a block and get help to lift it up to level and then measure it ,,but thought maybe some of you have already done so and can let me know what it is that I need ..

all that are there at the u-haul are girls and they said they couldnt help lifting it up so I could measure it ..

I have the 06 Silverado 4/4 with 17 inch tires ,,the one pictured under the posting about the popular wheels in this 99 and up forum ..