MonoKote will work fine over UltraCote, but as mentioned the UltraCote shrinks at a lower temp. Lots of folks use MonoKote over UltraCote because you can apply it over the UltraCote using the "windex method." UltraCote does not adhere like MonoKote does when you apply it with Windex.

The windex method is used by cutting the MonoKote out in the design or shape wanted, spray the back of the MonoKote with Windex, then position the MonoKote on top of the UltraCote. Use a credit card, or something similar to squeegee the Windex out from under the MonoKote and allow to dry overnight. If some of the edges have not stuck I have had success in using the iron to carefully touch around the edges to stick the MonoKote. After the Windex has dried, some like to wet a Q Tip with trim solvent and go around the edges of the MonoKote to help make it stick better.

Do a search of "Windex" in the plane forum and you will find some threads with much more detailed instruction than I provided.

On planes that I was not too concerned about having some bubbles under the MonoKote I have just ironed it down over the UltraCote. Even thought the UltraCote shrinks at a lower temp, it tolerates heat pretty good. I have never melted UltraCote when applying MonoKote over it.

Be patient. It takes lots of time for most of us to do a good job.

Good luck,

Eric