I had tiltons before it was cool... just kidding, once you put your feet on a set you'll never want to go back, you'll love 'em
Dave's right about the mounting though, total pain. Did you brace the floor at all under the pedal cluster?
How much was the twin plug conversion on the heads? I've been considering a twin plug setup for a while and it's more tempting now that there are better ignition solutions.