I have a Grey Gold 4 cylinder FE35 tractor . Am renewing the head gasket but am puzzled by the bolt /stud arrangements and torque settings given in the manual . The manual states a torque setting of between 95 and 105 Lb/Ft .for all the bolts / studs .However the bolts are 1/2 inch UNC and the studs are 1/2 inch UNF and so should have completely different torque requirements . UNF should have a lower figure than the UNC . Am not sure if my engine has been modified in the past or if its a variation of the 23c Standard Motor co. unit . Any clues anyone ?