How to make a part face the closest side of another part?

Alright, so before beginning this post:

• this is absolutely not the most efficient way to do this

• i want to understand why THIS method is not working, not for a more efficient method

• this project does NOT include the top and bottom surfaces of the init part

Alright so: I have a part which I will drag around my Baseplate - and a reference part which stays in a single position on the Baseplate. I don't want to use cf.new(vector,vector) at the closest side - I just want it to FACE the closest side, not the middle of the closest side.

Currently this is what I have, and I feel the issue lies in my handling of rotations toward the end:

local init_part = workspace.Init
local ref_part = workspace.Ref

local points = {}

local sub_x = init_part.Size.X / 2
local sub_z = init_part.Size.Z / 2

local two, four = init_part.Position + Vector3.new(sub_x,0,0), init_part.Position - Vector3.new(sub_x,0,0)
local one, three = init_part.Position + Vector3.new(0,0,sub_z), init_part.Position - Vector3.new(0,0,sub_z)

function determine_closest_side(from_part)
    local one_dist = (from_part.Position - one).Magnitude
    local two_dist = (from_part.Position - two).Magnitude
    local three_dist = (from_part.Position - three).Magnitude
    local four_dist = (from_part.Position - four).Magnitude

    local distances = {one_dist, two_dist, three_dist, four_dist}
    table.sort(distances)

    local closest = distances[#distances]

    if one_dist == closest then
        return one
    elseif two_dist == closest then
        return two
    elseif three_dist == closest then
        return three
    else
        return four
    end
end

while wait(1) do
    local cframe_construct = CFrame.new(init_part.Position, determine_closest_side(ref_part))

    local part = Instance.new("Part")
    part.CFrame = cframe_construct
    part.Anchored = true

    local y_orientation = part.Orientation.Y
    local solved_orientation = y_orientation - math.pi

    ref_part.CFrame = CFrame.new(ref_part.Position) * CFrame.Angles(0,solved_orientation,0)
end

If you want to experiment with this:

1) Make two parts in Workspace

2) Name one part Ref, and the other part Init

3) Put this script in SSS

4) Drag Ref around the Init part in Run mode.

Hopefully this is a decent explanation - but if you have further questions just make a comment.