i see, if its just for a short time you may be better off getting a few of those clip lamp holders, they go for about £3 each. only thing is you will have a plug for each lamp then. what about buying a 60watt cfl and just use the one. you can get them on ebay for about £5-10. 6400k as well. do a search for SAD lights and look for the cfl type.
if you were going ahead with the board idea then just connect them up in turn and put a plug on the other end. unless your using cfls that need some sort of adapter then you wont need one. the household screw in ones have their own control gear attached but you can get 2 and 4 pin ones and i think they will need separate control gear but they are much harder to get hold of, not worth it if your just going to be using them for a short while with seedlings