Is it an original playfield that has been restored/clearcoated? If so, it shouldn't need much. The screw holes should match up and the bit of clear that gets into them should not interfere. Maybe where there are wire forms to push into the PF you might want to predrill the holes but only slightly smaller than the wire.

If it is a new CPR PF then you may want to look at predrilling the screw holes. I have never done a new CPR playfield so I don't know from experience the size they drill and how tight that makes it for the screws. On the one Wade playfield I did for my QD Ken said to predrill the screw holes. I forgot the drill bit size he uses but it was perfect with his advice. Otherwise he said you could expect to break off screws in the new playfield because the holes are undersized. This was on a clearcoated new reproduction playfield and I didn't prepare it special in any way and had no issues with chipping.

The biggest issue is the quality of plywood that is being used in repro playfields is better/denser than the originals from back in the day. So the holes have to be limited in how undersized they are for a balanced fit.

As noted above you will want to slsightly countersink the surface.

Then push/hammer the screw through enough for a washer and nut to catch it on the back side. Continue to tighten the nut until it bottoms out. If not all the way seated on the top add a few more washers on the back side and continue to wrench the nut until fully seated on the top side.