Hi everyone, I am looking for some help on installing a shower base. I keep hearing there's a DIY section, but can't find it (maybe it's not accessible from mobiles).

I have to build out the walls a bit to accommodate the 48x36 inch base. Can someone tell me what the stud to stud dimensions should be? I don't know if it should be 48 inches after the drywall goes in, or just stud to stud. Once I know this, I can go ahead and pick out the shower base.