Why are these rotations acting weird?

I'm not going to past my script here since it's over 100 lines, but here is an example of what I am doing.

Part1 - Orientation = -68.91, 44.01, 44.01

Part2 - Recently cloned

I want to set Part2's Orientation to the same as Part1. Now through my script process, I have Part1's Orientation as X, Y, and Z (separate variables).

I then go to set Part2's Position and Orientation to Part1's...

local partCFrame = CFrame.new(PosX,PosY,PosZ)

local rotation = CFrame.fromEulerAnglesXYZ(math.rad(RotX),
                                    math.rad(RotY),
                                    math.rad(RotZ))

partCFrame = partCFrame * rotation

Now the Position works perfectly fine, but the Orientation of Part2 gets skewed somehow and I can't figure out why.

Part2 - Orientation = -42.15, 69.57, -16.96

Here is a picture of how it looks, the Blue is Part1, the Green is Part2. gyazo.com/64563902fa28379887c64adfa3221007