Almost everything applies to customization as well, including multiple teams.
As for how the multiple teams work, this will be in the upcoming SO errata:
Technician Type Modifiers table (p. 171)
*To a maximum of 3 teams per unit; maintenance on WarShips, JumpShips, Space Stations, DropShips and Large Naval Vessel Support Vehicles cannot be augmented with additional Technical Teams.
Change to:
*To a maximum of 3 teams per unit; use the highest team experience as the base experience level; extra teams must be at full strength, no more than one experience level lower and must have the appropriate Technician skill to help; does not apply to maintenance on Large Naval Vessel Support Vehicles and aerospace units larger than Small Craft.