Trek Fuel Disc adapter & hose routing

I have a trek fuel frame (stickers claim its the 2004 '90' model) that has a disc adapter. i'm wanting to run hydraulic discs up back and this isnt a problem however i'm wondering how i'd find out what size disc the rear of the frame could take?
I know 160mm would be more than adequate for xc work however i'd like a 180 and would consider larger if i could find one for the right price.
Any ideas how i could figure this out or will any disc be fine?
Furthermore the bike was designed for V style cabled brakes, how would i route brake hoses on a bike without a specific mounting point? I was considering trying to drill out the far left cable guide so it was hollow and try to get the cable through, but i dont think this will work unless i dissasemle the hose first and reassemble once routed.
Suggestions?
I know 160mm would be more than adequate for xc work however i'd like a 180 and would consider larger if i could find one for the right price.
Any ideas how i could figure this out or will any disc be fine?
Furthermore the bike was designed for V style cabled brakes, how would i route brake hoses on a bike without a specific mounting point? I was considering trying to drill out the far left cable guide so it was hollow and try to get the cable through, but i dont think this will work unless i dissasemle the hose first and reassemble once routed.
Suggestions?
The Frog: Lapierre Zesty 214 2010 - Upgraded - W.I.P
0
Posts
get suitable adapter for the discs you want, or the correct caliper (it is brake dependant).
buy a hose guide the fit in the cable guide.
Parktools :?:SheldonBrown
Would a hose guide solve my problem, the cable guide seems t be considerably more small than a hydraulic hose!
One of these?
http://www.allterraincycles.co.uk/product/118164.html
That does make sense!