Join Date: Nov 2014
Location: Marshfield, MA, USA
Your calculation is correct (168 inch lbs = 14 ft lbs) so no worries there. As far as accuracy, if you're shooting for the middle number, you should be OK. A little too tight, a little too loose, still within range.
You should buy a big one for the bigger torques. The inch-pound wrenches are limited, and with either wrench FWIW, shoot for the middle number and you should be good.
69 Convertible, 351W, T5, E-Brock Performer 351-W intake, Performer Plus cam, Holley 4160, power assist, dual exhaust, 4-wheel manual drums.