thanks dave as i hoped the grp frame will fit inside the metal back end
im thinking of using the grp tubes to support the bottom of the tank ditch d13's and affix the ends of the grp frame to the two dignals behind the suspension arms/arch
so i can have a tank aprox 990 long and of std hight maximising boot space as well as tank space
also joining the dignals off the back of the roll bar to the top off the tub rails for extra support
i think it will work out about 50% bigger than the orignal and leave just as much room as std tank
