once theyre on, theyre on. Think of them as ink with adhesive behind them. I dont use brake fluid I just sand with 1000 grit to get the old letters off and any scratches, clean with alcohol, dry, lay down the decals, then spray with SEM clearcoat
I used these on my wiper switches, cruise stalk, and we actually designed the fist check engine light for ls swaps using these decals. They are all oem toyota embelems and fonts and are measured by calipers down to the 0.00mm... I know this because i measured a lot of them for him haha