If I remember correctly (tell me if I am wrong), it's not the actual length of the hose that differs between drums and discs, it is the length of the screw piece that goes into the caliper/drum cylinder which is different.
I believe the drum pipe has a longer thread (length of thread) whilst the disc one is shorter.
Make sure you spray the brake unions on both side before hand - mine were so badly seized I had to redo the copper pipe that runs from side to side within the front subframe.
Do you have uprights from an 8.4" disc car or will you be purchasing a complete kit?
Ah, so there is a difference in the fittings between the two. I've been hearing different things from different people and was left confused.
Uprights?
The brake hoses linked earlier in the thread are correct. The brake end of the pipe seems to be universal so it can seal both using a copper washer on the outside face of a calliper but also up against a tapered union like if you were fitting it to a brake slave cylinder.
Twincam is referring to the hubs. Drum brake hubs have no lugs to attach a brake calliper to so if you're converting from drums, you'll need new hubs as well. Mini Spares sell a kit that has everything you need, it's not cheap though. Here you go.
Right, that makes sense. Yes, I have everything for the conversion. I bought a complete secondhand set that I rebuilt. It had the hubs, drive flanges, steering arms, calipers, discs and dust shields. So I'm actually good to go.
Although, it might be best to wait a couple of weeks and order the new brake lines first.