Just bought a 77 f100 flareside and have an instrument cluster question. I went on-line to order a new door data plate and purchased the standard build report at the same time. My question is the build report says that the truck has ammeter and oil pressure gauges, but the cluster in my truck has idiot lights. I know it is not difficult to swap clusters, but my research says that the wiring harness is different between the gauges and lights. How can I tell if they just swapped clusters or if they swapped the entire wiring harness? I gues the quick and easy question should be, what are the differences between the 77 instrument cluster wiring with and without gauges.
Thanks

 

The wiring all the way out to the voltage regulator is different. Take a look at your voltage regulator. If the 'I' terminal is blank as it would be with gauges, there's a hack somewhere. If it's not blank, then it's more likely everything was swapped together, but that doesn't mean there's still not a hack somewhere.

 

Thanks for the reply. I will pop the hood and check the voltage regulator when I get off work. At this point I am hoping someone just swapped the cluster and the idiot lights just don't work. I already have a clean 100MPH cluster with gauges. Just not sure what year it is out of.

 

I don't mean to hijack the thread, but i've not heard of this before. How/where would I go to purchase a new data plate and purchase a build report? Thanks.

 

pretty sure the 100mph are 76 and earlier. my 74 and 76 had them and were black, my 78 was silver and 85mph. i dont know about the 77 year model

 

I got them from Martiauto.com. Tag was 30 and the standard report was 15. The report took 2 days to be e-mailed to me, the tag is 4 to 6 weeks.

 

Thanks Eviiltim72. By the way my 77 F100 has the 85 mph speedo w/gauges FWIW.