its a very simple process and you can keep your master cylinder as i have. Simply strip all the modulators, belts and front brake lines from the vehicle. Then just call a mobile mechanic (or do yourself) to run new copper brake lines from the master cylinder to the t-pieces inside each front arch. The main difference on the abs master cylinder and the non abs one is that the abs one has two extra outlets for the modulators. So with this you simply get a suitable pipe and just run it from the one extra outlet back into the other extra outlet which just makes the brake fluid recirculate in the system Then job done.
There is a diagram on here to show how to route the new brake lines, if you do a search you should find it. Or pm me your email and I will send it to you.