Removing oil pan w/headers: 71 Duster?

cant say for sure but i would take the engine out to get the pan of,took me about 5 hours of frustration to change a oilpump with the engine still in the car,however i have a deep sump with a much longer pickuptube and i had to unbolt the headers for this since there was no way to lift the engine with the TTI headers bolted to the heads to make enough space to get the pan down far enough to slide back.