+1 for isopropyl mix with water 50/50 dilution ratio.
+1 for Goo gone
+1 for clay, use clay lube at the same time. Let the clay do the work.
+1 stoners tarminator

Try Stoners Tarminator if that doesn't work clay then Iso and then Goo gone if the other two aren't doing too much. Do not work in the sun. Working in the sun means increased heat. Look for a shaded area.

Good luck, keep us posted and always keep in mind more does not always mean better in terms of using chemicals on your car.

 

Not sure if I would use something that 'removes paint' on my paint That's just me though!!

 

For tree sap that has hardened, carefully scrape the top of the spot off with a plastic razor blade to expose the softer sap inside. The remaining sap can usually be removed by soaking with Isopropyl Alcohol (or Stoner’s Tarminator®) wet the area with the product by soaking a micro fibre towel and allows it to remain on the surface for 3-5 minutes, then wipe with soft dry towel.

 

None of the products mentioned are formulated with a solvent agressive enough to remove paint