Which fuel tank...multi vent or single?

Hi all.
Just going through the motions of removing the twin under-slung LPG tanks and fitting a boot tank and then replacing the micro fuel tank with the normal one...except i am still unsure which one it should have.
Its a 1990 EFi 3.9.
I think it should have the multi vent but perhaps one of you could confirm this please. Thanks.

It will be multi vent but 1990 is on the crossover from metal to plastic tanks. Is the fuel filler cap high up on the wing? If yes, should be plastic tank.