You can select your bath panels from several available materials, and the way you will use them and their installation in your bathroom should be considered before you buy panels. Acrylic panels are useful and they are waterproof. They are sheets molded by the bath companies, in a way that they can appropriately accompany the bath ranges. The variety in sizes is not great, and won't allow much height adjustment. You will need them to be submitted for fitting when the bath is.
The bathroom fitter needs to check that the height won't affect the requirements for plumbing, and the floor should be more or less level. Allow for the floor's thickness, too. Some panels of acrylic have clips that will fit on the floor or under the rim of the bath. Make sure that the sub frame is made so that it keeps the panel tight, and helps to reinforce it. The panel combinations in the end and front panels are easy to install, since most of the panels have molded ends to help them fit. You can use Velcro to help hold the panel where you want it, to allow easy plumbing access. The cutting can be done with a fine tooth saw if it is needed. After the installation, you can clean the panel with mild soap and water. If you notice any small scratches, you can polish them out with rubbing compound.
Wrapped or veneered panels can often be found with loose plinths that will allow for adjustments in height. The thickness is usually between a half and three-quarters of an inch. This means that with some construction work, the cradles and legs may obstruct the panel. Make sure to check first, and take into account the plinth on the back of the panel, which doubles the thickness at that point. You want the panel to be flush when it is installed. If the panel protrudes over the rim of the bath, this can result in water possibly collecting on the ledge and eventually penetrating the bath panels.
These panels are generally solid, but you should have a floor sub-frame and wall battens to secure the installation. The loose plinth is important here as well. The items should be installed in the correct order, which is bath, plumbing, floor covering and then bath panel. Leave the panel until last and make sure that it fits exactly.
To adjust the panel's height with the loose plinth, measure the height and allow room for the plinth to affix to the back of the main panel. There will normally be an overlap of about an inch and a half, to give you the maximum height. Next, measure the bath height from the floor to underneath both ends of the rim.
Don't cut the bath panel, if it can be avoided. It may compromise the finish's water resistance, and allow water to gather behind the finish, which can cause it to lift. It may also allow water to seep into the panel's sub-structure. Be especially careful when you fit a detailed or sectioned panel into an area that is recessed, by cutting each side of the panel equally. This will ensure that the bath panels remain centered.