Keep in mind that assembly are very much like structures from a connectivity stand point, they are an fyi distinct from the main commodity flow.
To your question there are two approaches for bank meters : with features and with association connectivity. With features (aka. service pipes at real location or just a straight line) you utilise geographic coincidence to link the meter devices to the end of your service lateral. With association, you place a connection point (which is a synthetic asset) at the end of the service lateral, and associate all meter devices to that connection point. If the end of your service lateral is some other device like the service valve, then that connection point is not required.
The assembly would typically only contain the meters and any in-between assets from the end of service lateral. That modeling of the containment is optional and an aside to the flow of the ressource.
