Silicone wax on a vehicle, advise on how to remove it?

[Martyn]

i would start off by telling them to not get it waxed in the first place

[Simon Worrall]

No. You will need to use Wax and grease remover first – then alcohol after.

[Robert Lambie]

Definitely advise against them waxing the vehicle, prior to installing vinyl.
As has also been said, wax remover with a micro-fibre cloth, followed by Isopropynol alcohol.
“IF” your graphics crosses a recessed area of any sort. clean in the recessed area with one of these “domestic” cleaning sponges with a soft scouring pad. better if it’s a bit worn already.
use this with your degreaser/wax remover in the recess, then again, follow-up by cleaning with microfibre cloth with Isopropynol alcohol.

[Jeff]

abrasive sponge. good tip rob!
wax can cause real problems if you have to fit vinyl on a freshly polished car. your customer must understand that!