[JMay]

Kev,
         Correct printed vertically, and as you stated less hassle on the clean up. I draw the support structure for each shell based on some common parts like I beams and cones as below. The support structure is anchored to a 1mm thick plate to ensure it doesn't lift its skirts and float round the bed. 

   

   

I cut the back off the shell off and print that separately to avoid having remove (and clean up) a lot of support from an external face and give the major section a flat side to work from as shown. 

This is the DBR 1 (grey) , new ribs and posts (red) supports (blue). 

Printed using the Esun PLA ST filament which is stronger and a bit more flexible than standard PLA using following settings on a CR10 Mini (forerunner to the Ender 3)

0.1mm layer
Bed temp 62 C
Nozzle 204 C
Speed 60 mm/s except outer wall at 40 mm/s
Support & bed adhesion set to none.

Print time 8 hours.

Cheers
            John

P.S. As stated else where, I firmly believe in Fit for Function.