this problem can be easily solved by using a jewellers saw [sometimes also called a jewellers piercing saw] This tool consists of a steel bow frame in which a very fine [less than 0.5mm] cutting blade resembling a fine wire is held under tension. a wide range of blades with thicknesses and teeth sizes are available to suit the job at hand.
using this tool it is a very simple task to remove parts without stress on the part or the risk of breakage. with some practice it is possible to remove parts to the point where no clean-up is required.
the same tool is also superb for removing PE parts from the base sheets.
a good source for the jewellers saw is MicroMark, who also have a range of blades in stock. Alternatively this excellent tool is available from any reputable jewellers supply house.
this is one tool that should be in every model builder's armoury.
above all have fun









