gold already is an actual item that can have a weight attached to it. literally all you'd have to do is open the window and change a number.
have you really not modded anything since Morrowind? everything's completely different now bro. we livin in the future and [censored].
I checked before posting this, and I haven't a single gold coin in my inventory. It just says "Gold 9000" in the bottom right of the UI. Sure, there may be single gold coins lying around the world, but when you pick them up they just disappear and add one to your gold number. Don't they?
No, I never did get the hang of oblivion modding, and I haven't tried it for Skyrim yet.