The beam meets the hand at it's center. I want it to be the end of the beam touching the hand. How?

while wait() do
        if on ~= "n" then
                beam.Size = Vector3.new(0,((hit.UpperTorso.Position - plr.Character.RightHand.Position).Magnitude)-1,0)
                local num = (hit.UpperTorso.Position - plr.Character.RightHand.Position).Magnitude
                local targetPosition = hit.UpperTorso.Position
                local pos = (plr.Character.RightHand.Position)
                beam.CFrame = CFrame.new(pos, targetPosition)
                local rotatedCFrame = CFrame.Angles(math.rad(-90), 0, 0)
                beam.CFrame = beam.CFrame:ToWorldSpace(rotatedCFrame)
            else
                beam:Destroy()
            end
        end

Currently, the beam meets the hand at its center. I want it to be the end of the beam touching the hand. How? I have tried many things.