I have reverse engineered design automotive part along with Rapidform XOR3, and I can upload and open the solid model part in Fusion 360. However how do I import the align 3d scan data to the assembly in fusion 360?
You can import the 3d scanned mesh directly to your Fusion 360 part model.
Just click Insert and there you will find number of file format that support in import to part design.
Insert -> Insert Mesh