Any idea how big a job it is to remove the ABS?

My main concern is how much work needs to be done to re-route/replace the metal pipework. Got a mate who works for Pirtek so I can get it done if there's some templates or something out there

 

Why do you want to remove it? I know it's not the best system in the world but for a road car I'd say it's better to have it than not, plus it can / will cause problems MOT time.
If it's for a track / race car then that's a different matter, I'm doing mine at the moment and the only way is to remove everything, except the flexi's !!!,(but if you've not got Goodridge then fit them at the same time) then source a RA MC (these have 3 outlets instead of the usual 2) then make up the new metal pipes 1 to N/S F 1 to O/S F then the third MC outlet to the rears T'd to split it between the 2 rears, you can use the OE MC by T'in the 2 outlets F + R but it's better to use a RA MC and keep the fronts seperate..
Also you will need a brake bias valve to decrease the rear braking power and balance the system, all in all it's quite a bit of work but worth it for a track based car, for a mainly road car I'm not sure it's worth it even if you can get around the potential MOT issues