Replacing rear wheel bearing, '90 135GLi

Need to replace a rear wheel bearing on my '90 135GLi. 

Have replaced a lot of wheel bearings throughout the years, but never seen a construction like this. I do have the Haynes manual and access to a hydraulic press. 

Any good tips? Should I replace the inner single-row bearing as well, or only the outer double-row? All the kits I seem to find only contains one bearing..