Assuming you want to evenly space the parts along the same path, you can do this:
Make a sketch somewhere in the original ipt file that gives you the x y and z distances from the point of origin of the base part to the point of origin of the first part in the array. Then go to your assembly file and open the Paramaters and "Link" those x,y & z part Parameters to the assembly file. then use Parameter distances to drive your PATTERN (vis., JD above).
If you want to arrange the parts erratically, you are stuck using constraints. Or you make a 3D or multiple 2D sketchs in an IPT file, insert that into the assembly, and use the sketch connection points (or work features) as the origin points of each part instance in your assembly file.
That's how I would do it.
Cheers ...
... Chris
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