WR-LPU is a lower solids coating, which wets out surfaces very well. Because of this, it can wick under ordinary masking tape giving you less than desirable results. Specialty tape for jobs like auto refinishing can be a better choice than architectural painters' tape. On the other hand, it can actually be easier to paint without tape if the masking gets too complex.
Consider trying it on a practice piece to ensure you have a good technique before applying it on your project. There are two methods that have proven to be successful using masking tape:
1) Allow the paint to dry overnight and then carefully cut along the tape line before pulling it. This should help prevent the paint from lifting.
2) To avoid having to cut the tape, allow the LPU to cure to a barely tack-free state then carefully pull it, and the paint won't lift.
Finally, for thin stripes, consider using automotive striping tape, rather than paint.