My '73 had two plugs - one in the normal spot then another garboad [sp] style plug on the bottom of the hull.  I've never heard anyone else say thiers had two plugs so I'm wondering if the previous owner installed the 2nd plug underneath to solve the problem you are talking about?  I don't know that I'd worry about it too much.  Having 2 plugs you are 2 x more likely to forget one (ask me how I know).  Use a cement block or something under the trailer jack to tilt the boat more while on the trailer would be my suggestion. 
  
Here is what I think on your fuel tank dilema.  Check out Reelapeelin's '75 model.  He made 2 custom seat boxes with two 40 gallon tanks inside for a total of 80 gallons - all forward enough not to cause a weight balance issue.  I would go that route before putting all that weight on the rear.  I don't think you'll be happy with the ride.  But, of course, this is only an opinion.  But seriously, take a look at Reel's customization before you decide.
		 
		
		
		
		
		
		
			
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1994 Wellcraft V21
			  
		
		
		
		
		
	
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