Are you sure that's the same Ramp ??

Excellent work..Nifti cleans anything - EXCEPT - Playfield plastics !

Here's a tip - Remove the two metal ball guides, and "regrain" them with 360 grit wet/dry sandpaper and windex.. They will look new. If you have a buffing wheel, polish the four screws - if you don't have a buffing wheel - Grab some Brasso, a couple of drops on a rag and then rub the head of the screw on the rag.... Put it bacj together - Would take 5 minutes 

Never spray anything on the playfield.. First pass of a filthy playfield - Grab a old ice cream container and half fill with water.. Spray nifti 3 or 4 times into the container and dip the rag in to the container - clean the playfield.. This prevents any liquid going directly on the playfield..