Hi Martin,
This is the stuff I have used on both cars, the Roadster was done in 2010. If you want to chat about it give me a call.
p.s. I would recomend you use their complete system to ensure the tank is rust free and clean. Frost are also a great company to deal with.
https://www.frost.co.uk/por15-car-bike-motorcyle-fuel-tank-repair-sealer-473ml/?gclid=Cj0KCQjw0rr4BRCtARIsAB0_48PLXA-5nqDESChH4lZXx1N1ajVaa56GRuKjb-g1d0ewf9UfEDLYfmMaAtTEEALw_wcB
Keep safe Philippe
Philippe Allison