[Closed] New front mech? Changing cartridge BB to external BB

Hi. I'm just about to start my first bike build. I'm taking stuff from my old bike and fitting it to my new frame (Orange G4). But I'm wanting to upgrade my cranks from shimano octalink to shimano deore so I'll need to change my cartridge BB to an external cup type (hollowtech). My question is will my existing front mech still be ok? Because I will have the width of the BB cup in between the frame and chainset to contend with. Any help will be greatly appreciated. Don't wanna have to keep spending more and more money on extra stuff. Cheers. Mark