Torquing (NOT TWERKING) in tight spaces

I am installing my Intake and Exhaust manifolds and my Service manual says to apply 15-20 ft. lbs. of torque.

My problem is that of the 13 I need to torque, I can only get to 5 with a torque wrench. The rest can only be accessed with a box wrench.

I took my Torque wrench and placed a hex head bolt adapter on the end of it, fitted that thru the closed end of a box end wrench and dropped the torque value of the wrench to below the settings I had and then moved them back up testing each increment on a bolt that I was able to torque properly until I reached the same break setting.

Is this a sound method or will my bolt pressures be off? I am afraid of over torqueing and breaking the manifold (again).

Thanks!!

Cory

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