Because of significant floor rot, I ended up totally redoing our rear bath. The enclosed picture will show you how the wooden platform relates to the tub drain.
I rerouted both the supply lines and drain lines, so your plumbing won't look exactly like the same. The tub drain and platform however, had to go back in their original locations since I reused the tub, and the two panels on the curb side. The tub drain is kind of hard to see, but it's right next to the angled edge of the platform. I ended up building a new countertop and putting in a new sink.
Not all the black lines in the picture are waste lines, some are supply lines with pipe insulation covering them.
Good luck with the rebuild.