Might check to see if something like Naval Jelly is available and test it in just a small section of the painted area and time the application to a short period then repeat if needed.
Light colors often look like other colors due to exposure, the elements and age. Once down to the paint you will need to lightly sand, steel wool or other wise remove the top oxidized surface to get a better look at the true color
White, pink, tan, and yellow can all look like one another if you skip this step.
Last option would be to use lye on a section of each stripe (it will remove it completely leaving nothing) it will bubble and expand in the bubbles but will let you see the color as it removes. By doing only one smaller section of the larger stripe you will get a chance to try other options. Oven cleaner (over here) is a handy way to purchase it. Spary it carefully in a container (like a glass jar) and apply it with a brush. Watch and take care with eye, hand and skin protection from splatters and spray
