it will work, a nova plug is longer than the os 8 but it wont cause you any problems from being shorter. you can also try the odonnell 99 if you can get them. it is a long plug and works well in the nova.
I don't think you want to be using a mc-59, thats a little hot, especially if you run 30%, if you are using 20% yeah you could use it in a pinch. When I had mine, I used OD 99 plugs with great success.