I need Chevrolet P30 Chassis wiring diagrams which I Jul 24, 2013I need Chevrolet P30 Chassis wiring diagrams which I expected to be available and they are not. I am sitting with an inoperable motor home at Lake Tahoe. This is a 1987 Chevrolet P30 chassis built into a 1988 Holiday Rambler Alumalite XL class A motor home. Complete 73-87 Wiring Diagrams News: As of April 1, 2008 All Classified forums require a Site Supporter subscription. Chassis Electrical and Ignition (Moderators: VileZambonie, Irish_Alley, bd) » Complete 73-87 Wiring Diagrams Here are the complete wiring harness schematics for the 73-87 series. These are HUGE jpgs so you may want to save and print them off.