Hi,  manual says for the two 14 mm bolts to tighten to 36-43 ft lbs when installing blades.  Is a torque wrench necessary?  Don't have much need for one other than this and perhaps when changing spark plugs.  Any suggestions which torque wrench to purchase ... 3/8' or 1/2", brand, range?  Assume don't want one with too high of an upper number as it may not be all that accurate at 40 ft lbs.   Thanks
	
		
			
		
		
	
			
			 
				 
 
		 
 
		