It is not real clear what manuals apply to the Chevy P30 Chassis so I complied a list to make it easier for everyone.
Basically there is a Service Manual and a Component Overhaul Manual. The confusing part is that the P30 chassis is included in the Light Duty Truck manual. It was only in the late 80's that GM moved the P chassis to a seperate manual. It is also my understanding that, it was not until the late 80's that GM moved the wiring diagrams to a seperate manual. There is a general service manual that provides a world of useful information. It covers mid 70's through 1992.
Please be aware that Bisko Manuals does cary some of these on CD-ROM which are a lot cheaper.
-------- Year | --------------------- Chevrolet Light Duty Truck Service Manual | --------------------- Chevrolet Light Duty Truck Overhaul Manual | --------------------- Wiring Manual | --------------------- Light Duty Truck Fuel Drivability and Emissions Service Manual |
-------- 1974 | --------------------- ST 330-74  | --------------------- ST 333-74 | --------------------- ST 357-74 | --------------------- --- |
-------- 1975 | --------------------- ST 330-75 Supplement Use with ST 330-74 Base Manual  | --------------------- ST 333-75 | --------------------- --- | --------------------- --- |
-------- 1976 | --------------------- ST 330-76 Supplement Use with ST 330-74 Base Manual  | --------------------- ST 333-76 | --------------------- --- | --------------------- --- |
-------- 1977 | --------------------- ST 330-77  | --------------------- ST 333-77 | --------------------- ST 357-77 | --------------------- --- |
-------- 1978 | --------------------- ST 330-78  | --------------------- ST 333-78 | --------------------- ST 357-78 | --------------------- --- |
-------- 1979 | --------------------- ST 330-79  | --------------------- ST 333-79 | --------------------- ST 357-79 | --------------------- --- |
-------- Year | --------------------- Chevrolet Light Duty Truck Service Manual | --------------------- Chevrolet Light Duty Truck Overhaul Manual | --------------------- Wiring Manual | --------------------- Light Duty Truck Fuel Drivability and Emissions Service Manual |
-------- 1980 | --------------------- ST 330-80  | --------------------- ST 333-80 | --------------------- ST 357-80 | --------------------- --- |
-------- 1981 | --------------------- ST 330-81  | --------------------- ST 333-81 | --------------------- ST 357-81 | --------------------- --- |
-------- 1982 | --------------------- ST 330-82  | --------------------- ST 333-82 | --------------------- ST 357-82 | --------------------- --- |
-------- 1983 | --------------------- ST 330-83  | --------------------- ST 333-83 | --------------------- ST 357-83 | --------------------- --- |
-------- 1984 | --------------------- ST 330-84  | --------------------- ST 333-84 | --------------------- ST 357-84 | --------------------- --- |
-------- Year | --------------------- Chevrolet Light Duty Truck Service Manual | --------------------- Chevrolet Light Duty Truck Overhaul Manual | --------------------- Wiring Manual | --------------------- Light Duty Truck Fuel Drivability and Emissions Service Manual |
-------- 1985 | --------------------- ST 330-85  | --------------------- ST 333-85 | --------------------- ST 357-85 | --------------------- --- |
-------- 1986 | --------------------- ST 330-86  | --------------------- ST 333-86 | --------------------- ST 357-86 | --------------------- --- |
-------- 1987 | --------------------- ST 330-87 | --------------------- ST 333-87 | --------------------- ST 357-87 | --------------------- ST-376-87 |
-------- 1988 | --------------------- ST 330-88  | --------------------- ST 333-88  | --------------------- ST 350-88 WD  | --------------------- --- |
-------- 1989 | --------------------- ST 330-89  | --------------------- ST 333-89 | --------------------- ST 350-89 EDD  | --------------------- --- |
-------- Year | --------------------- Chevrolet Light Duty Truck Service Manual | --------------------- Chevrolet Light Duty Truck Overhaul Manual | --------------------- Wiring Manual | --------------------- Light Duty Truck Fuel Drivability and Emissions Service Manual |
-------- 1990 | --------------------- ST 330-90 (First year of TBI)  | --------------------- ST 333-90 | --------------------- ST 350-90 EDD  | --------------------- ST 502-90SB Supplement |
-------- 1991 | --------------------- ST 330-91  | --------------------- ST 333-91 | --------------------- ST 350-91 EDD  | --------------------- ST 502-91SB Supplement |
-------- 1992 | --------------------- ST 330-92 | --------------------- ST 333-92 | --------------------- ST 330-92 EDD |
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