"Apparent from the front and rear lights, the GT1 shares many components with its series production counterparts, but puts them together in a more competitive way...."Originally Posted by EJ25RUN
"The GT1 was based on the 993 bodyshell, but with modified exterior panels and a substantial roll-cage that also supported the engine, gearbox and suspension. This helped Porsche avoid neccessary crash testing and reinforced ties to the production cars..."
"...a complete interior included sport seats and a full dashboard from the 993 line..."
From supercars.net