EmonCMS Full Install on HDD

Returning after a loooong break, (someone seems to have moved all the furniture…), and want to make a new install of Emoncms on a new emonbase bought from the shop (not fussed about migrating my old data). But since i’m starting from scratch I want to use an external HDD from the outset. I have a shiny new pre-built SD card, but I am unsure whether I need to follow the instructions at Install Emoncms (effectively starting with a blank sheet) or whether I can more easily “upgrade” the low-write version to a full version. The guide at Moving to External HDD tells me how to move the OS to an external drive, but will that also upgrade me from low-write to full?