I have Hedman 4 tube Hedders on a '68 Firebird 400 and there is adequate room to easily remove and reinstall the stock starter.
I had those headers and my stock starter fit fine too....after I had the car for a week, my starter went out, I bought one of those $29.99 O'Reilly's starters just to get me by for awhile....4.5 years later, it was still working. When I installed the 2" primary & 3 1/2" collector headers from MadDog, no way stock starter was going to fit, so when I got my RobbMc mini, I gave it to a guy I met at a gas station who had just bought a '67 bird who was having hot start issues....