Boat interiors face weather conditions like sun and moisture that cause the upholstery to crack, crumble and fade. The upholstery of a boat usually falls apart long before the rest of the boat, so replacing the upholstery extends the years of enjoyment you get from your investment. Replacing the boat upholstery is physically hard work but it is not especially complicated. Finding the right replacement upholstery and disassembling the old interior are the two hardest parts of the job.
Find a replacement interior; check with local upholsterers, the boat manufacturer, Internet auction sites and local boat-salvage yards. Select upholstered pieces that are covered with a quality, sun-protected marine vinyl. Higher-quality upholstery fabric will stand up to weather challenges better than low-grade vinyl. Facing a weather challenge is precisely what the UV protected fabric is designed to do. If the new boat upholstery is sewn it should be stitched with sun-protected thread.
Find the place where each piece of upholstery is fastened to the boat. It should either be a screw, snap or clip that is hidden behind the panel. Unscrew--or gently pry--the panel or seat away from the boat. Make a small note on the back of each piece as a reminder of where it was before it was removed. Compare the old upholstery sections to the new, to ensure they are the same. Copy the note from the back of the original piece onto the back of the matching new piece.
Hold the new upholstered piece against the boat, checking to see if screw holes (or other fasteners) line up. Screw the new panels in place but do not tighten screws completely. Step back and confirm that the panel looks straight. When the upholstery section is in place, confirm that the screws are going in straight and finish tightening them.