Need info on XS400R Seca

I just picked up a near basket case XS400RK - 1983. I would like to get as much info on this bike to prepare me for the restoraton and conversion to a cafe/streetfighter look. Please share what you know or have done to this model.

A couple of questions;

1. Is there another Yamaha that used the same fuel tank? Mine's got a rust hole and it might be better to replace than weld a patch

2. I need a tray for the battery and did not see one on the parts diagrams - anyone know what to use?

3. Is there another model that uses a wider rear wheel that will be a direct swap? Mines 2.15" I like at least a 3.0"

My plans are to install a dual Dominator headlight, bar end mirrors, Mini CF blinkers, eliminate the pixie looking tail fairing, sccop the seat and 2:1 Exhaust with a snappy black pearl paint job.

I'll be posting pics of the builds progress.