TTI Headers with Pro Comp Speedmaster Heads

My '67 Barracuda with a 340 needs an upgrade on intake/exhaust. I've decided to go with the Edelbrock RPM Air Gap intake and want to get the TTI headers but when I called TTI, they said they have no knowledge what or if they would fit due to the Pro Comp Heads I've installed... Does anyone have TTI headers installed on Pro Comp heads and if so; Were they difficult to install without cutting out the car body? And how is the access for oil filter? Any modifications with the steering/chassis components ?