Any tips for Undercarriage detail of Shelby Cobra?

[rgnbull1227]

The car is spotless now and I would like to keep it that way. Any tips and products to keep the underside looking as it does today?
Thanks!

[Lowejackson]

I am not sure about its availability outside of the UK but this might be worth a look Cavity Wax | Order Dynax-UC For High Protection Rust Proofing (http://www.bilthamber.com/cavity-waxes/dynax-uc) it is a clear underbody wax