The quick answer is that the rudder castings and the mast are the same, all else is different.
You could replace the mast, boom and sails on an 18-2 with same from a regular 18, but the bridle wires and shrouds may be a bit different in length. I have not done this swap, but have read about some that have.
As dis-similarities go the 18-2 is:
Wider, so the crossbars and tiller connector are longer
Has a square boom that is also longer and has an internal 4:1 outhaul car
tramp is bigger
mainsheet blocks are bigger
Sails are larger
Rudders are shorter due to centerboards
Hulls are very different
As you can see, not much to interchange unless you replace all that is aloft.
I have a collection of useful 18-2 data here if you end up buying it:
http://thebeachcats.com/pictures/?g2_itemId=88542
Sheet In!
Edited by klozhald on Sep 27, 2012 - 01:20 PM.
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Sheet In!
Bob
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Prindle 18-2 #244 "Wakizashi"
Prindle 16 #3690 "Pegasus" Sold (sigh)
AZ Multihull Fleet 42 member
(Way) Past Commodore of Prindle Fleet 14
Arizona, USA
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