Don't know your layout, but on our 190E I had to remove the pressure regulator at both gas connections to the fuel distributor on top of the airflow meter, and the bolt that clamps it down. The hose that connects its vent to the breather hose is designed to contain gas that would spurt out if the diaphram ruptures. Gas flow was momentary, but avoid disconnecting the INPUT gas line to the regulator.
The pot was held on with four T-15 torx screws covered by a pair of pry-off plastic covers.
'91 MB 190E 2.3
'08 RAV4 Ltd 3.5
'83 Lazy Daze m'home 5.7