dash swap questions

[75K5]

swapping from a 75 dash to a 78 dash that has a tach. I have a few questions

1. The 75 dash has a clip behind the speedo that secures the speedo cable. How do you secure the speedo cable behind the 78 dash? I don't see any way to lock it in place. See attached pic comparing the back of my 75 dash vs the 78 dash

2. I think I want to convert to a electrical oil pressure gauge. Any idea what the sender part number is? And where would I install it on a 5.3L Vortec motor.

3. Where do I connect the tach signal wire on my 2009 Tahoe 5.3L motor?

Thanks!
Brian

 

[blazer74]

First off the 75 has amp Gauge , the 78 has volt gauge = smoke, fire, burn.

Look at the circuit board where the plug from the harness
goes, it is different.

Do NOT plug it in and put power to it.

 

[75K5]

Thanks for the feedback. I was planning to run the voltage gauge. i figured it would just work, but if they changed the pinout I'll have to trace it back. It should just need 12V+ and ground to work I would assume.

Brian

 

[blazer74]

Amp gauge is wired with two 12volt + and compares draw vs charge not like volt gauge
Just +/-. Need to rewire and check the rest with wire diagrams, fuel gauge is obviously in a diff place with a tach cluster.

The amp gauge also has its own fuses (2) in the engine compartment.

 

[dyeager535]

IIRC you'll have to change the speedometer cable to fix that particular issue.