a baseboard having a front end and a rear end, the front end and the rear end defining a chassis depth;

a busbar module having a chassis-side busbar connector positioned on a rack having a rack depth; and

a rear wall positioned along the rear end of the baseboard, the busbar module being stored entirely within a gap of the rear wall in a first configuration;

wherein the busbar module is adjustable such that the chassis-side busbar connector mates with a rack-side busbar connector in the first configuration or a second configuration, the first configuration having the rack depth being approximately equal to the chassis depth, the second configuration having the rack depth being greater than the chassis depth; and

wherein the busbar module is configured to retract and expand, thereby alternating between the first configuration and the second configuration, the busbar module being retracted between the rear end and the front end the baseboard in the first configuration, the busbar module extending outside the rear end of the baseboard in the second configuration.