We're about to have the outdoor carpet in our screened porch replaced. What is there now is the common "grass turf" type with a woven polypropylene backing glued to exterior grade plywood. I plan to remove it myself so I wonder how's the best way to go about it? Any hints etc would be appreciated. BTW I know it has to be perfectly smooth so there will be no telegraphing bumps and ridges. I also recall 2 or 3 gallon of floor leveling goop was needed to level an area where a room expansion had occurred. Thank you!