Hello
A standard 4948 correspond to a configuration of a 4510 chassis with supervisor 5 and 8 times 4506 Line Cards (6x1GE).
Or the Catalyst 4948-10GE corresponds to a configuration of a 4510 chassis with Supervisor 5-10GE and 8 times 4506 Line Cards.
In both cases all 48 Port delivers true 1gigabit bandwidth without oversubscription.
So all guides form the 4500 series and reference manuals can be used.
Cisco understand under fix configuration the hardware is not modular
Otherwise are hardware configurations with a chassis, supervisor and x times 4506 line cards named modular.
hth
