I can't help with that I'm afraid, I'd keep my eyes out for a Chute if I was you, quality, seriously strong frame which should be able to take a 5 inch fork, I've been debating getting a chute or a roast for a while, good luck.
Sorry for the late reply, it's my brother, he has a 1998.5 (I think) Nunu, I wouldn't put 5 inch forks on it, hence me asking, but it's a good bike none the less. I'm not sure how much he would need to part with it, but it was just an idea.