Why isn't my Build System able to align the build able parts with the plot GridSize of 2??

My part of my script here is supposed to use a gridsize of 2 and it is oriented correctly but when you move the part it out aligns the part with the grid on the floor is there a way to make the part aligned with a vector?? or Cframe??? Please help if you can!

local RunService = game:GetService("RunService")
local UIS = game:GetService("UserInputService")

local Player = game.Players.LocalPlayer
local Char = Player.Character or Player.CharacterAdded:Wait()
local Mouse = Player:GetMouse()
local Camera = workspace.CurrentCamera
local PlaceObject = game.ReplicatedStorage.BuildEvents.PlaceObject

local GivenPlot = game.ReplicatedStorage.BuildEvents.GivenPlot
local PlaceObject = game.ReplicatedStorage.BuildEvents.PlaceObject

local posX 
local posY 
local posZ
local YPos = Vector3.new(0, 75, 0)
local Rot = 0

local Object
local Plot
local PlotO
local ButtonObject = script.Parent.ScrollingFrame.Soil.ImageButton

local CanStart = true
IsPlacing = nil
local CanPlace = nil

GivenPlot.OnClientEvent:Connect(function(plt)
    Plot = plt.Name
    pltPX = plt.Position.X
    pltPY = plt.Position.Y
    pltPZ = plt.Position.Z
    PlotO = plt.Orientation
    PlotX = PlotO.X
    PlotY = PlotO.Y
    PlotZ = PlotO.Z
end)
local function Placement()
    if IsPlacing and CanPlace then
        PlaceObject:FireServer(posX, posY, posZ, Rot, Object.Name, PlotX, PlotY, PlotZ)

        IsPlacing = false
        CanPlace = false
        CanStart = true

        Object:Destroy()
    end
end
local function TopDownView()
    if IsPlacing then
        local playerPos = Char:FindFirstChild("HumanoidRootPart").Position
        local cameraPos = playerPos + YPos

        Camera.CFrame = CFrame.new(cameraPos, playerPos)
    end
end
local function Movement()
    if IsPlacing and CanPlace and not CanStart and Mouse.Target and Mouse.Target.Name == Plot then
        Mouse.TargetFilter = Object

        posX = math.floor(Mouse.Hit.X / 2 + 0.5)*2
        posY = math.floor(Mouse.Hit.Y / 2 + 0.5)*2 - 1
        posZ = math.floor(Mouse.Hit.Z / 2 + 0.5)*2
        Object:SetPrimaryPartCFrame(Object.PrimaryPart.CFrame:Lerp(CFrame.new(posX, posY, posZ) * CFrame.Angles(0, math.rad(Rot), 0), 0.2))
        Object.PrimaryPart.Orientation = (Vector3.new(PlotX, PlotY, PlotZ))
    else
        return Mouse.Hit.p
    end
end

local function StartPlacementSoil()
    if CanStart then
        Object = game:GetService("ReplicatedStorage").Soil:Clone()
        Object.Parent = workspace
        Mouse.Move:Connect(Movement)
        IsPlacing = true
        CanPlace = true
        CanStart = false

        Mouse.Move:Connect(Movement)
    end
end

local function StartPlacement(obj)
    if CanStart then
        Object = game.ReplicatedStorage:FindFirstChild(obj):Clone()
        Object.Parent = workspace

        IsPlacing = true
        CanPlace = true
        CanStart = false
    end
end

local function Rotation(input, GPE)
    if IsPlacing and CanPlace and not CanStart and input.KeyCode == Enum.KeyCode.R then
        Rot = Rot + 90

        Object:SetPrimaryPartCFrame(Object.PrimaryPart.CFrame * CFrame.Angles(0, math.rad(Rot), 0))
    end
end

Mouse.Button1Down:Connect(Placement)
ButtonObject.MouseButton1Click:Connect(function()
    StartPlacement("Soil")
end)
RunService:BindToRenderStep("Input", Enum.RenderPriority.Input.Value, Movement)
UIS.InputBegan:Connect(Rotation)