What size Ubolts?

Should be 3" x 7" long. Mancinis has stock ubolt kits, ones with the waffle pattern under the "u" for $43 plus shipping. Just installed a set on my 8 3/4, perfect fit with s.s. springs. Less thread showing on the pass side due to extra 1/2 leafs. Torque nuts to 45 ft/lbs