Irwin 28 built in the 70s

[little breeze]

Hello everyone, does any Irwin owners know where I can find info on a Irwin 28 possibly mid 70s. I want to know what keel design and what years they have changed. the boat is in the water and the inherited owner cant give me a answer he is not sure. Can anyone tell me what keel designs and what years they have changed and related to which models. Thank you Don

 

[jssailem]

Try this site.
http://sailboatdata.com/viewrecord.asp?class_id=904

And in 1976 here is the MK IV
http://sailboatdata.com/viewrecord.asp?class_id=1058