I think your all wrong guys,
The injectors will fit in both rails, but the rails will only fit on the heads they were made for.
The reason people bore out rev 2 rails when fitting rev 3 (or bigger) injectors is for increased flow volume, but this is only necessary with higher HP builds.
But the rail only holds the injector so the flow volume wouldnt be affected in the rail is bored? Surely its the injector size that deals with the flow volume?
Ive looked into the rev3 ecu swap and they have all bored the fuel rail or used a wolfkatz one.
The rail feeds the injector it doesn't matter how big the injector is if the rail cant feed it, trust me on this one.
you can bore out the rev2 rail to 8mm & feed from both ends, rev2 & 3 injector spscing on the heads are different so the rails are not interchangeable