I’ve noticed that maxton do a rear lip spoiler, side skirts and a rear diffuser for the Scala. Thinking of getting some or all of these for my Monte Carlo. 
anyone got any of these who can give a testimonial?  I had the rear lip spoiler on my m140i and it was very discreet. Not too Lairy..

Hi @Simcity47  I have the entire Maxton Kit on my Scala.  The front splitter is awesome, and can be fitted using factory screws under front bumper, although not sure it will fit the MC.  Side skirts I got bodyshop to fit as they have to be fitted to metal bodywork and I wanted to ensure they were sealed properly, again not sure these fit the MC model as there are skirts already on.  Rear lip spoiler is a really nice little extension to the spoiler, piece of cake to fit and really robust.  The rear skirts are easy to fit too.  However the rear valance is oversized and sticks out by about 3-5mm along its length.  To push it as far back as possible was awkward and actually put it under so much stress that it has snapped under a small knock.  So will be doing a custom diffusor. 

Thanks. Will go for the roof extension and see how that looks. Especially with some eibachs on it.