Where to put tensioner/idler pulleys?

I am trying to finish up my custom Novi 2000 bracket, but the cogged belt I have currently is too long. It is a Jason 1440mm with 8M pitch. So far I can either find a replacement for that or a belt that is 1280mm long. I was going to try to put the idler pulley and the tensioner pulley on the outside of the belt, but I cannot do this with the current belt because the pulleys would be too close and the shorter belt will be too short. I liked this idea because it gave me more belt wrap around the blower pulley (I know not as big of an issue with cogged belt. What is the proper way to route the belt around the idler and tensioner pulleys? I am thinking of putting the idler on the inside and the tensioner on the outside at the top of the belt. Any help would be appreciated.

I think I answered my own question last night. With some extra help, we mocked it up, and the belt I have looks like it is the correct length. The idler will ride on the outside of the belt at the bottom and the tensioner will ride on the outside of the belt at the top. Looks like I should have plenty of room for adjustment and the belt wrap should be fine. Hope to get pictures shortly.

Definatley snap some shots, sounds sweet man.