here i found this in another thread
Originally Posted by tmsoko
Agree with the radiused edges. ALWAYS do this. Just round off the cut end with a grinder. Very simple.
As for the parts, I think I found the receipt and it came back to me how cheap the plates were.
U-Bolts for larger tube: W704611-S436 List $19.11
Plates 1L5Z-5798-BA List $4.72 (really)
I remember it being around $60 total (OK, it was ~$70 with my employee discount), and I also remember how remarkably cheap the plates were.
btw You can probably use stock LVL2 Ubolts if you wanted. the price is different now but that is the part number that i used.