When I put a 4' level against the side walls/studs or in the middle of the tub to check if width of the tub is level , the bubble is exactly in the middle. Which tells me that the sided of the tub is level.
If I put the level in the middle of the tub or all the way to the left of the tub (lenght wise) , the bubble is exactly in the middle. But if I move the level towards the right (lenght wise), the bubble is not exactly to the middle, shift slightly to the right almost touching one of the 2 lines in between the bubble.
I know you can use mortar or shims to correct the issue..But when testing adding a shim in one location or the other, the issue persist.
Does the bubble need to be exactly in the middle for every inch of the tub or is ok if is just leveled when checking the sides, the middle for both lenght and width.