What you need to do when installing over lays is to make sure the area that you intend to cover is clean and has a surface that will take the decals adhesive. What I am saying is that you need to make sure the surface is totally flat (especially the mansion area) because this area will have small crevices around the inserts. The only way to get round this is to mask off the outer area (area that's not being covered) and reduce it by around 8mm (Area that you are flatting back is smaller than the decal) and sand down the area that is being covered. This needs to be done until the said area is totally smooth and without any imperfections. You don't need to sand back to the wood just enough so you have a totally smooth and flat area, this will also help with the adhesive giving it a good key to stick to. If needed you can us a 2 part filler (very strong) filler if there are deep crevices around the inserts to bring it back flat BUT! make sure that the inserts are not covered with any filler once sanded as the light need to get through. Make up a water and washing up liquid solution (around 25=1) and spray the playfield before laying the decal onto the area, this will give you the time you need to move the decal and match the new decal with the playfield. Once you have positioned the decal where you want it you need to squeegee the remaining water out from underneath the decal until it all gone and then leave well alone in a warm room for at least 24 hours until the decal adheres to the playfield.
Don't be scared its not such a hard job to do, just take your time and don't rush anything if you do have any questions and if you need any more help just ask.
As for the decals they should come ready cut to size and you should not have to trim anything.
Once you have installed the decals the best way to seal them is with with clearcoat. Otherwise the edges will start to loose there colour with ball play over time. I have done quite a few playfields over the years using this method and had no trouble at all.
Hope this helps.
Darren.
