Topic: jo meek preamp and rme pre amo question

hey guys first of happy new year to all you rme lovers ! i have a fireface 400 and also a joe meek preamp .
i was wondering {a} should i go into the main mic pre's from the joe meek or the inputs at the back ?
           and also {b}if i go in 0 db from preamp do you think i should keep the gain right down on rme or keep it at 0db too  ?
sorry i know its a mouthfull but i would really appreciate any help . many thanks in advance guys ! cheers tabby