I am not sure where you would put the extra tank in a Beetle and still
have room for your passengers.
You can get tanks that fit in place of the spare wheel, but I guess
that would only be suitable for the 1302/1303 Super Beetles. Plus I
would not like to think what would happen in a serious front-end
accident.
--
Howard Rose
1966 VW Beetle 1300 Deluxe
1962 Austin Mini Deluxe
1964 Austin Mini Super Deluxe
http://www.howard81.co.uk/ (cars on website)