We have installed a shower tray in a corner of our bathroom and need to tile the walls. We plan to do this before fitting the walls of the shower enclosure. Now the angle between our walls is more than a right angle and so the tray is right up against one wall but there is a gap about 3/4" wide at the front on the other, narrowing to almost nothing as it approaches the corner. The wall with no gap is solid whilst the other starts off solid in the corner for the first 6" and then turns into plywood, where a door has been blocked up. The tray has a tiling upstand, which sounded convenient when we bought it but probably only makes it more difficult to do a neat job: without the upstand it might have been tempting to stuff the gap with sealant, but we won't be able to hide the fact that the tiles will sit on the upstand at the corner but will be way outside it at the front. Any suggestions? One thing I've thought of is that we could possibly unscrew the plywood and pack it from behind, on one side more than the other, to bring the angle between the walls closer to 90 degrees and narrow the gap. The shower valve has been installed within the ply wall, since this was more convenient than burying it in the solid wall. So if we did alter the angle of the wall, would it matter that the pipes etc. would (presumably) no longer come out perpendicular to it?