It depends on how serious you get, but if you start with a Fox, you're starting with more modern (better?) technology.  Also the fox is a lot more aerodynamic than the classic. Do you really want to cut up a classic to make a serious drag car? 
		
	
		
		
		
		
		
		
			
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				68 coupe, 302 w/ Edelbrock performance parts, T5, 3.55 rear, needs paint!
			 
		
		
		
		
		
		
	
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