I don't recall anyone posting about having success with the blower on-soapy water test, and I don't see how it could work in our vehicle without some modification. We have a rear vent that is always open. This would allow any air coming in to instantly go out without creating any sort of pressure at all. I suppose you could try duct tape over the vent panel, but air may find another path to the vent and you would never be sure if no exterior bubbles meant no leaks.

Mark