60" Long Print on Wood, Best Method?

I have no experience screen printing, but I have some lettering I'd like to print on some boards. The lettering is a single color, white, ~60" long and it is going on a stained piece of pine.

My question is, what is the best way to do this? I can build a rig to hold the board and screen(s), how do I make or where do I buy a screen that is 60" long? Is it better to split it into a few separate prints?