Remove seat. 2 bolts hidden under rear, so have to pull the padding/seat edge at back forward to see them. Remove front plastic tank trim....2 bolts on the sides....one each side. Once out, that price slides forward and off. Next you will see 2 more bolts that hold tank down in the front sides of tank. Remove those. Now the tank lifts up from the front and pivots. Then u will see the air box top. Remove the 8-9 screws.....including the one in the center that's hard to see. Lift off air box lid. Remove and replace filter.
Look up YouTube video. FZ8 and FZ1 are identical