Trying to change a tools grip through a script?

So someone on discord asked someone to help them with tool stuff, so I replied and said sure and the issue is that the tool rotates when sitting down. I've tried making a short script to change the angle when sitting down but it was in CFrame instead of Vector3. I have never used Vector3 before and just looked it up and tried Vector3.new but I have no output now. I then changed the script to be plr.Character.Humanoid.Seated instead of Sit. Here's the local script inside of a tool so far:

local plr = game.Players.LocalPlayer
local Tool = script.Parent

Tool.Equipped:Connect(function(a)
	
	if plr.Character.Humanoid.Seated == true then
		Tool.GripForward = Vector3.new(-0.383, 0.924, 0)
		Tool.GripUp = Vector3.new(0.924, 0.383, 0)
		
	elseif plr.Character.Humanoid.Seated == false then
		
		Tool.GripForward = Vector3.new(-1,0,0)
		Tool.GripUp = Vector3.new(0,1,0)
	end
end)

Tool.Unequipped:Connect(function(b)
	Tool.GripForward = Vector3.new(-1,0,0)
	Tool.GripUp = Vector3.new(0,1,0)
end)