Corsa C Z14XE 1.4 Removing Inlet Manifold for Alternator

[90Ninety]

 

 Im having a go at replacing an Alternator on a Corsa D 2004 1.4 . According to a service manual the inlet manifold needs removing , said manual is here .  Seems to make sense since the Alternator terminals are hidden behind this manifold .. My guess is  I need to de-pressure the Schrader valve by depressing the valve , and then  just unbolt this line with a regular spanner ( the manual states a special tool )? 

 

Also how do I remove this guy below ? Didnt wanna break it