Usually I pour some of the R-3 brake fluid into a glass bowl and holding a model with one wing I dip the second one into the fluid. It has to stay there for a while then using a thick brush I start removing a paint still keeping the model wing dipped in the fluid. When all is removed I use a soft , soaked with the R-3 fluid, rag for cleaning "washed" area. Please remember that after cleaning a model has to be washed up with a warm water and soap. If I use the WAMOD fluid I remove a colour with soaked soft rag.
Also I suggest making a test with a piece of the model sprue frame dipped in the R-3 fluid. Just in case if the R-3 could damaged the polistyrene.
Also I suggest making a test with a piece of the model sprue frame dipped in the R-3 fluid. Just in case if the R-3 could damaged the polistyrene.