Wit most Lotus, any modification which adds performance, reliability, or durability is still mostly considered a plus. +2's usually came with the most powerful stock version of the twink available, like big valve SE spec etc. I honestly don't know what is available for bolt on modifications like cams. How come the headlights are down? It should take vacuum for that on a '70. If it has not been run for a few days I would expect them to be up. I had a '67 which used vacuum to open them, but my '70 it should be the other way.