I have 1 x 172 Cup hub, and 1 x Ph1 172 hub on mine at the moment, both are identical.......there is no difference at all.....My wheel definitely isnt sticking out further either...
Plus im running a cup driveshaft on the Ph1 172 hub side, and a 172 Ph1 driveshaft on the Cup hub, it all fits perfectly....
From my research on driveshafts (mainly because of issues whiteleys had) I found from physically comparing the different shafts myself (172 ph1, 172 ph2 and 172 cup) there were all the same length....only 182 was different because of the bearing on the back of the block...
The wishbones are the same dimensions too, from checking these at the same time. The only difference with those is some variants have different castor (positioning of the balljoint holes) it seems.....