The serial number 73348120 tells us that this bass was stamped on the 30th November 1978 (day 334), at the Gibson Kalamazoo plant, and was the 107th instrument stamped that day.
This RD bass has the first series switch configuration, as detailed in the diagram (left). See the RD Artist technical page, for a view of the mode switch from inside the body of the bass; it is not a simple three-way toggle. The technical page also shows the two-switch system that replaced it. The disadvantage of this early switch system is that expansion/compression could not be used simultaneously with the bright mode. On later models it can.
Ebony finish was available from 1977 until 1981.
The bass pictured has mark V active humbucking pickups, Gibson 3-point chrome bridge, and Schaller BM machine heads.