[sir_pudding]

I'll note that trying to directly covert a world where pistols can can red mist elephants and deliver orders of magnitude more energy than contemporary tank guns is probably not a good idea, but it is possible in GURPS. You could say that 2.5 MDC is equal to DR 637 in GURPS based on the M72 LAW in both systems. This is likely to produce a very silly game.