Can I use motor coater in place of blacktop, and if so do I use the same procss - rustseal wait 2-4 hours, rust seal wait 2-4 hours, then motor coater all in same day?

Yes, you can top coat RustSeal with Motor Coater. The process you described should work beautifully for you. In general, there are three effective ways to top coat RustSeal effectively so that the coatings bond & fuse together. 1) Apply your top coat once the second or final coat of RustSeal is dry-to-the-touch and does not leave a fingerprint (usually 3-10 hours depending on temperature and humidity). 2) Let the second or final coat of RustSeal fully cure (at least 24 hours), scuff the RustSeal with 300 grit, then apply your top coat. 3) Let the second or final coat of RustSeal fully cure (at least 24 hours), dust the RustSeal with Fusion Self-Etching Primer (http://www.kbs-coatings.com/fusion-self-etch-primer.html), let the Fusion cure for 30 minutes, then apply your top coat. You can feel free to choose the method that will work for you. Please let us know if you have any additional questions.