Personaly I normally go from least aggressive method up. It depends on how long the tree sap has been there but you may be in for a couple hours of work especially on the top.

Heres a small article on top cleaning... I if you do decide to use rubbing Alcohol I would use it in a very tiny area as it made fade or stain the top. I have used Ragtopp cleaner with a a medium stiffness brush and light scrubbing to get it out before. Oh and butter will stain your top so dont try it.

http://www.autopia-carcare.com/inf-cabrio.html


On the paint my favorite bug and tar remover is TAR-X by carpro... its expensive but it works awsome and wont damage your paint and a little goes a long way. You can also try a auto store bug and tar remover or Rubbing Alcohol just make sure you dont let either dry on your paint and that you wash it off immediately as some of them can cause damage ( Guy used some stuff from pep boys on his front bumper and it took all the paint off his plastic trim). Whatever you do try not to use a ton of pressure or your going to end up with tons of swirls and hairline scratches that will need buffed out.