Light monitoring system rpo U46

[My68SS]

Hi, did the light monitoring system option include a chrome housing on both fenders or only the drivers fender?
Which lights were monitored via the fender mounted housing?

[JohnZ]

Housings on both front fenders and in the lower center of the rear window - headlights and park/turn lamps were monitored in the front, and outboard taillamps and license light were monitored in the rear.

[My68SS]

Thanks for that John. I thought that must be the case with the front ones.
Unfortunately some time before I bought the car it suffered a damaged LH guard and that housing was missing. Someone had replaced the damaged guard with an RS guard [pop riveted tabs into it to mount standard headlamp housing  :/ ] and the light monitor housing was either lost or not transfered to the replacement guard 

I think I'm up against it finding another one of those! Might be quicker for me to hand craft another one somehow.
Also, one of the rear tailight lamp holders has a standard plastic back shell which doesn't have the socket for the optic fibre to plug in.

[ogbean]

Nah man... they ait that hard to find because they were options on most 1968 chevy models. Set yourself a favorite search on ebay... i see the front setups on there bout every twos week... short time ago i saw an NOS front assembly got fot round $150 i think. Just keep an eye out rand one will pop up!

[My68SS]

Excellent!! I knew the fibre system was used on many chevy's, corvette etc. but thought the fender housing shape/style  may have been a bit different between models.

What about the tailight harness, was that the same or even similar in other chevy's such that I could at least get the correct lamp base's off it?
Thanks for your help 

[My68SS]

Which lights were monitored by the rear pod, seems the two outer red lens fibers are for the tail/stop lights, not sure about the center one?

[JohnZ]

Which lights were monitored by the rear pod, seems the two outer red lens fibers are for the tail/stop lights, not sure about the center one?

See my post above - only the outer bulb was monitored.

[My68SS]

Ah sorry JohnZ, I'm chasing around too many forums atm, loosing the plot!   
Ok I had a look at mine and can't see were or how the fiber gets from inside the trunk to the light, or even were it connects into the plate light housing??
Is the rubber grommet for the wire meant to be a two hole affair, one for the wire and the other for the fibre?
Maybe mines been replaced with a standard plate light assembly?

[JohnZ]

The routing, connections, and holes for the rear portion of the system are all shown in the Assembly Manual in section U46, Sheet A3 and A4.

[My68SS]

now why didn't I think of that!!  
cheers

[My68SS]

ok got it. I'd missed that extra hole in my rear panel to the left of the number plate, and all my light sockets are correct. The reason I thought I had one wrong socket [earlier post] is when I first got the car, someone had poked that fiber into one of the turn signal lights, but that never added up for me of course - [monitoring one turn lamp??]

The only thing not quite right is my number plate light housing doesn't have a hole in it for the fiber. May have been changed?
Did the housing come with the hole for a fiber, or did the factory drill an extra hole at assembly?
If you 'read between the lines', the manual suggests that the housing hole should already be there, as for the rear sheet metal hole it says " 9/16" Dia. hole - drill at asm."
No mention is made that a hole of a particular size needs to be drilled in the housing.

[JohnZ]

The Assembly Manual will tell you that too - the license lamp for U46 was unique, P/N 916664, and the standard license lamp (UPC 12, Sheet C4) was P/N 910967.

[My68SS]

Ok got that thanks, though in my book it quotes 911242 for the standard lamp asm. [upc 12 - c4] and 916273 for the U46 option lamp asm. [ upc u46 - a3]??

[JohnZ]

The numbers I gave are for the '69; don't have a '68 A.I.M. handy.