Coolant recovery tank

To run a street car on the track you need a radiator catch on the overflow.
I have on the Demon a 1qt transmission bottle I zipped tied to radiator support below the top on the side of the radiator. I drilled a hose in the cap after washing the bottle clean. Tight fitting (does not take up a lot of room) and you don’t even see it.
Cheap too. Option for you. Maybe the not the best option but will work. Side note: make sure your drain tube is smaller than your hole. This allows air to escape as fluid comes into the bottle.