Thanks guys that very helpful. I'll nip the nut up when my new torque wrench arrives my old Britool Torque wrench is a good 50 years old but the scale starts at over 30 lb ft so decided to treat myself to a lower range wrench that I will need for cylinder head bolts etc.
I had the Britool recalibrated a good 30 years ago when it was fitted with a new spring - I always undo the adjuster so there is no tension at rest. Sadly I tend to use impact torque sticks on our 4 wheeled vehicles - its just so easy!