I second bb's advice and would put a good polypropylene film in place of it. Film capacitors can be used anytime you find a electrolytic of 4.7 and lower, without worrying about polarity.
The only time polarity comes into play is if the film is big. Then it can pick up noise through induction and you would, though testing, find out which end has the outer foil and that end goes to ground, or the previous stage, depending on how its used.
Some bigger films have a black band to id the outer foil end.
I also use a 1uf. Panasonic polyester film like
ECQV1H105JL if you can find them. They fit well and are small.
If you put your fingers around an input cap, you may hear it and know its bass- ackwards, but for the small films under 400 volts, its not nessesary to do it unless your caps are next to a strong magnetic field
John