Someone else can confirm, but... metro/vented discs will push track out further. I assume you already trimmed out an inch of fender on the forward side? Is it fouling the fender or the arch, or both? I ended up using 6j on the vented setup and it was pretty flush with sportpacks. 

Good one 6464. My car gained several degrees of turn with every fraction of inch height. Reminds me of the 18 wheeler that couldn't make it under the bridge; he let some air out of the tires. Your solution is the most logical.

jack up the front

As title really, I am trying to narrow the track width to accomadate my 13" 7J's

I have replica sportspack arches fitted with the wing cut, metro hubs, drive flanges, vented discs with 1.5 neg degree bottom arms and Mini steering arms and Spax lowered coilovers fitted.

The problem is the 175/50 tyres catch the arch with very little lock applied.

Any suggestions most welcome but I wondered IF,

1. I changed the vented discs to non vented, if so do I need to change the drive flanges

2. Change the hubs from Metro to Mini.

3. Use 6J's on the front.

As I say all suggestions welcome