G,day Alchemy84 70 -72 ftlbs is correct depending on the year (I think) in any case 2ftlbs won't make any difference, the taper needs to be true, use some valve lapping compound & lap it in, I havent exackerly figured out the easiest way of holding it yet, I'm gonna try a belt type holder, like a oil filter removing tool for a car tied to the frame or footpeg or whatever else lends it's self. Very important I'm told to make sure that taper is true or it shears the key. 247's hold a special place in my heart also my shed, there's 6 of 'em in there (4 basket cases) also a 172 (nother basket) & if I can stop smoking & save the pennys there'll be a few more before I'm done. VIVA MONTESA