Thought I would share this with you.
Ever since I purchased by new bike this year I have felt that the stock XT disc brakes 160 front and rear were a little imbalanced and a underpowered at the front, especially for a 5" travel bike.
I posted the question to BM a couple of months ago and received some mixed suggestions on how I could upgrade to 180mm on the front. Most sounded bodgetastic to be fair.
Now that Shimano have released a 180mm DEORE calliper for 2006, I decided to have a search of the Ultimate Pursuits website to see if there was an adapter that you could buy. Bingo.
Part no 817 3100 - SPRE IS Mt adapter 180mm FR is what you need. I purchased a Hope Mono Mini disc to go with it. All are fitted and the difference in braking is immediately noticeable. Total cost £35. I would recommend this upgrade to anyone.

Incidentally – I didn’t appreciate this but rear callipers mounts are 20mm inboard of the fronts. So I could have bought a 160mm Hayes rear adapter and simply fitted it to the front. Noticed this when the new part arrived and it was identical to the rear adapter. This also tallies with other manufacturers (Hope) calliper sizing.

Hope this is of some help.

EBC kits work perfectly for me so far, cheaper and Zero Hassle, Hope C2 like rotors which I like.

Wondered what the difference between front and back was, never got around to working it out, thanks, hmmmm :)