Tyres for TR6

[john_worthy_at_wca-0606@mail.workcover.nsw.gov.au]

     Previously I asked the lkist for assistance in calculating the overall 
     gearing of a TR6.  The question stemmed from the fact that the TR6 I 
     recently purchased had 185/65 tyres on it.  Got a number of responses 
     to my question and all agreed that 185/65s were totally inappropriate.
     
     I now want to replace these and was set on getting a set of 205/70s 
     until I read on the VTR maintenance page an article on TR6 tyres which 
     says:
     
     "I would stay away from the 205/70-15 or shorter profiles (like 60 
     series) unless you don't care about how accurate your speedometer is. 
     If you're into autox you might want the 205/70 because they are 
     roughly 2% smaller diameter."
     
     This person promoted the 215/70.  Now I'm totally confused.
     
     If the original tyres were 185/80 then the tyre width was 148mm.
     205/70s are 143.5 while 215/70s are 150.5.  It would seem 215s are 
     closer to original.  However. they border on overtyring the rim and 
     look big.  What advice can listers give me?
     
     John
     72 TR6