There may be some M-Line info here:
http://a100.gov.bc.ca/appsdata/epic/..._53_15491.html
But even much of that is out of date since those are planning documents (not as-builts)
- i.e. the preferred route map (only half of which is provided) shows a future Grandview Station @ Nanaimo, which was eventually dropped (no accommodation for it).