I go from polish to sealant when using Duragloss 101, or 111 as they both have a level of cleaning ability. I assume the cleaners in the formula, along with the action of the pad on the machine negate any residual oils left by the polish.

A lot of my one step polishes are done with PF2500, and DG101.

Unfortunately, I'm not sure about Power Lock. What do the directions say? Do they indicate the need to strip the paint before application?

If it doesn't say to do that in the directions, you're probably good to go.