how do I weld one player's parts to another player's parts?

I need help trying to weld two parts of different players (their head and another one's head) I know welding is difficult with player to player connections but I can't figure anything else out. Anyone here that can help me? Also my script is just basic welding script (setting their part1 and part0's and parents but I'll post it anyway)

game.ReplicatedStorage.Moves.SPgrab.OnServerEvent:Connect(function(player)

	if player.Backpack:FindFirstChild("Grab") then
		local char = player.Character

		local hum = char.Humanoid

		local right = char:FindFirstChild("RightHand")

		local root = char:FindFirstChild("HumanoidRootPart")

		local grab = hum:LoadAnimation(game.ReplicatedStorage.Animations.SpecialMoveAnims.SPgrab)

		local punch = hum:LoadAnimation(game.ReplicatedStorage.Animations.SpecialMoveAnims.SPpunch)

		hum.WalkSpeed = 3

		if right then

			grab:Play()

			local fin = false

			wait(.1)

			right.Touched:Connect(function(hit)

				if hit.Parent:FindFirstChild("Humanoid") and fin == false then

					if hit.Parent.Humanoid ~= hum then

						local enhum = hit.Parent.Humanoid

						local target = game.Players:FindFirstChild(hit.Parent.Name).Character

						local instance = Instance.new("Weld")

						instance.Part0 = right

						instance.Part1 = hit.Parent.Head

						instance.Parent = right

						punch.Looped = true

						punch:Play()

					end
				end
			end)
		end
	end
end)