[Jack21]

Yes, Ford and GM number the cylinders very differently. And the firing order for your 302 is determined by the cam you use. 289's and early 302's used one firing order, 5.0's and all 351W's used a different one wit factory cams. An aftermarket cam may use a late firing order on an earlier engine.

If all else fails, remove the valve covers, turn the engine over by hand, and check the valve opening sequence to see what your firing order is.