Hi Josh,
I have fitted a few roof linings, including an ebay one. All quite easy just need to fit all of the steel hoops into the lining seams and then fit the ends of the steel hoops into the roof frame, with the nylon plugs. Note the nylon plugs must be fitted into the holes around the roof frame otherwise the steel hoops wont seat properly.
I usually use a spray adhesive like 3m and spray around the edge of the lining and around the edge of the roof frame and then wait 10 minutes. Once the adhesive is tacky I then loosly attach the rear and then stretch the lining and loosly fix the front, making sure the steel hoops are in the correct location and sitting at 90 degrees to the roof frame or vertical. This may require some moving of the lining at the front and the rear, which is why they are only loosly attached. Once the lining is centralised I start fitting one side and then stretching across to the other side so the lining is tight. then once the lining is fitted to both sides I check for any creases and adjust the lining to remove these as much as possible, bearing in mind that once the fitting of the lining is completed you will still have some small creases which will eventually smooth out by parking the car in the sun for a few hours. Onec the sides have been fitted and the lining has been fitted against the roof frame I then make sure the front and rear has been fitted and pressed against the roof frame. Once thee roof lining has been all smoothed out and you are finished I then wrap the lining around the window and door frames and then trim with a knife around the outside of the metal frame, so the roof lining is on the inside of the car and wraps around the metal and will be held in place by the window rubbers. Next you can fit the small pieces at each rear quater panel, which may require some new cardboard templates to be made and then fit the piece around the bottom of the rear window. You will also need a very sharp knife and make some carefull cuts and fitting around the top of the front A pillar and the top of the B pillars. Also cut a small hole for the wiring of the interior light and pull out the wires.
All finished now so sit back and admire.
