Good Tigers don’t hang about long, hence the lack of adverts for them. Best years to stay away from the Purple Passion Glue is to go for a 1977-79 model. Having said that it is recognised that after 20 odd years if a plane had a tendency to delaminate it would have done so by now. There is a simple repair for dealing with delamination using flush riveting. The CAA have a repetitive delamination AD inspection to be carried out every 150hrs and takes about 1 ½ hrs to do a whole plane. It is a very easy to inspect a aircraft to see if it has the purple glue as long as you take it to a Grumman experienced engineer.
The best place to get a full answer to your question on Glue or for that matter any other Grumman related query is to go to the Grumman Gang Achieve site
www.grumman.net/archieve/ and do a search for Purple Glue, you will get all the replies for similar question over the last 5 years. I have looked and you should find the answer to what you want, too many to repeat here.
If you are serious about owning a Tiger I would highly recommend that you join the Grumman Owners Club (AYA)
www.aya.org who are a valuable source of information on all things relating to this type of Aircraft.
As past regional director for Europe of the AYA and part owner of a 1976 Tiger with blue glue, please drop me a line and I will give you my contact details for an in-depth answer to your questions.