I would still remove what I can of the wax using goop, wd40, ect, then with alcohol. Then apply real thermal compound.

I guess you can use acetone (nail polish remover), then alcohol to clean off the acetone

Clean the mating surfaces completely with a low residual solvent (High-purity isopropyl alcohol or acetone will work) and a LINT FREE cloth. (i.e. lens cleaning cloth) If another thermal compound has previously been applied to the heatsink, the mounting surface should be thoroughly scrubbed and cleaned with a xylene based cleaner, (Goof Off and some carburetor cleaners) acetone, MEK, mineral spirits, or 99% pure isopropyl alcohol. It is important to keep the surfaces free of foreign materials and NOT to touch the surfaces (a hair, piece of lint, and even dead skin cells can significantly affect the thermal interfaces performance, especially on modern small core CPUs as the surface area is already severely limited). In addition, oils from your fingers can adversely affect the performance by preventing the micronized silver fill from directly contacting the metal surface. (Fingerprints can be as thick as 0.005")