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The site was - Sylvania Lamp Guide (http://www.sylvania.com/auto/carapp/) for searching other generations.

SYLVANIA Lamp Replacement Guide

CHEVROLET 5th Generation El Camino

Low beam headlamp
Part number = H4656
Upgrade Part Number = H4656ST
Silverstar High Performance Halogen Upgrade - Whitest, Brightest, 100% Street Legal
Upgrade Part Number = H4656XV
XtraVision Halogen Upgrade - Three times brighter & twice the life of standard

Upgrade Part Number = H4656CB
Cool Blue Halogen Upgrade - White Hot; Super Cool; 100% Street Legal
Upgrade Part Number = H4656LL
Long Life Halogen Upgrade - Lasts 6x longer

High beam headlamp
Part number = H4651
Upgrade Part Number = H4651ST
Silverstar High Performance Halogen Upgrade - Whitest, Brightest, 100% Street Legal
Upgrade Part Number = H4651CB
Cool Blue Halogen Upgrade - White Hot; Super Cool; 100% Street Legal

Parking light
Part number = 194NA
Part number = 1157A
Upgrade Part Number = 1157AST
Silverstar Signal Lighting - Complete the Look: Crisp, Clean, Style
Upgrade Part Number = 1157ALL
Long Life Upgrade - Up to twice the life of the standard lamp

Front turn signal
Part number = 1157A
Upgrade Part Number = 1157AST
Silverstar Signal Lighting - Complete the Look: Crisp, Clean, Style
Upgrade Part Number = 1157ALL
Long Life Upgrade - Up to twice the life of the standard lamp

Rear turn signal
Part number = 1157
Upgrade Part Number = 1157LL
Long Life Upgrade - Up to twice the life of the standard lamp

Tail light
Part number = 1157
Upgrade Part Number = 1157LL
Long Life Upgrade - Up to twice the life of the standard lamp

Stop light
Part number = 1157
Upgrade Part Number = 1157LL
Long Life Upgrade - Up to twice the life of the standard lamp

License plate
Part number = 194
Upgrade Part Number = 194LL
Long Life Upgrade - Up to twice the life of the standard lamp

Back up light
Part number = 1156
Upgrade Part Number = 1156LL
Long Life Upgrade - Up to twice the life of the standard lamp

Front sidemarker
Part number = 194
Upgrade Part Number = 194LL
Long Life Upgrade - Up to twice the life of the standard lamp

Rear sidemarker
Part number = 194
Upgrade Part Number = 194LL
Long Life Upgrade - Up to twice the life of the standard lamp

Ash tray
Part number = 1892

Glove box
Part number = 1895

Dome light
Part number = 561

Step/Courtesy light
Part number = 631
Part number = 906

Under hood light
Part number = 93

Instrument-general
Part number = 161
Part number = 168
Part number = 194
Upgrade Part Number = 194LL
Long Life Upgrade - Up to twice the life of the standard lamp

Hi-beam indicator
Part number = 161

Seat belt indicator
Part number = 168

Brake warning
Part number = 168

Clock
Part number = 168

Directional signal indicator
Part number = 194
Upgrade Part Number = 194LL
Long Life Upgrade - Up to twice the life of the standard lamp

Radio dial
Part number = 73
Part number = 194
Upgrade Part Number = 194LL
Long Life Upgrade - Up to twice the life of the standard lamp