It should just be held in place with two tension clamps, one on each end. Use a decent set of pliers and/or multigrips to squeeze the tabs and slide them off. When you install the new one, either buy brand new tension clamps, or use good quality T-clamps or hose clamps.
Currently...
'03 Spyder 6MT - T28 inc...
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Previously...
'00 FD3S
'94 SW20 Bathurst R
'88 AW11
'92 SW20 G-Limited
'90 SW20 G
'91 SW20 Mongrel
'94 G Limited T-Bar
'92 GT-S Turbo