what do you mean you dont know if you can spray the plastic panels on a Rs50? course you can thats how they get colour in the first place

and people spray them black all the time its just using decent stuff
remove decals - use a hair dryer as they get really sticky so this melts the glue a bit and they will peel off with some time)
sand it - this will take a bit of work and a electric sander might make it quicker but get it sanded right down to plastic by hand
when sanding it use wet and dry and dip it frequently in a warm bowl of waterr and washing up liquid
use plastic primer and use good stuff, cover a wide area and make sure its BONE dry before applying paint - id apply a good few layers of plastic primer and leave it at least over night before applying paint, make sure you dont apply too much at once though coz it will run and waste you time.
colour of primer, choose your colour of paint first and see on the cap what colour primer it advises for best results - for example dark silver 04567 use grey primer for best results, if your gonna use a different colour on a different panel by another can of primer which suits the colour
paint, SPRAY FROM A DISTANCE as lots of people get impatient and go closish and get it all sprayed quick but then it runs whilst it drys and leave marks and looks rubbish so just spray it so it speckles slowly
and apply a good few coats of paint to get a good finish
laquer or top coat, buy a DECENT one that is noticably more expensive - may sound silly but cheaper laquer yellows in the sun so in summer it wont look nice it will look cheap n tacky so buy a decent top coat and apply small amounts as laquer n top coat is deadly if you apply loads as it will run like mad n smear paint ect so reallly small amounts but lots of coats
decals - now all the paint is finished fit your fairings and be carful not to scratch your hard work, with the panels fitted order some aprilia decals in desired colour and fit them where chosen and stick them on from centre outwards as to remove any air pockets and press firmly so they stay on
leave over night bewteen periods of different contents and make sure everythings bone dry bewteen coats, dont rush it and apply about 4 coats to each contents