Sides are double sided tape and screwed cannot come off.The original sides are slid off to the rear wheels,underneath are drilling points already marked out on the inner side 2 templates are supplied for the only 2 holes that are not previous marked you drill eight 5mm holes then the double sided tape coating is pulled back an inch place the new sill against the old loosely fix the screws in place then pull the rest of the tape backing off,tighten all screws the tape is very very strong stuff and will not come away as long as you make sure the original sill is clean (cleaning wipes and screws supplied.
The whole front has to come off which is only fixed on with the plastic push through clips, pull the wheel arch plastics away then release the whole off the front end wich is quite easy.The front end comes in 2 halves top and bottom ,unclip these then replace lower half with new part then replace whole section back onto car.
I was worried about damaging the painted front half because abit off brute force was needed when taking it off ,but its plastic and very very flexable basically it just unclips from the car.
Any thing else let me know .