Tachometer help!

[73 SGM Mach]

Ok I have 2 fairly straight forward questions and if anyone would be so kind to link any threads already discussing this please do so.
1. I have a Holley sniper with the hyperspark distro set up. My Factory tach does not work how do I fix this?
2. While I have the guage cluster out I need to replace the factory lights, old eyes dont see so well now, lol!. I was thinking blue led whats the best way to achieve this?
I'm thinking I will keep the stock appearance and have already updated the oil, temp, and alt guages to new VDO but need to update the blue lights.
From my other threads this is a Route 66 tour upgrade and trying to get all the parts together for next years trip!
Jeff

 

[c9zx]

You likely need an MSD tach adapter. Contact MSD tech help and tell them what you have. Chuck

 

[Doug's 73 Mach1]

About question 1, I had the same problem originally. I don't recall if this little black box came with the Holley EFI carb or the Hyperspark dist. See photos. Once I hooked up the little box, the factory tach worked. As I recall I talked to Holley technical over the phone to learn this is needed. The instructions that came with dist. or EFI unit were not helpful about this. I use a stock type coil.

 

[Hemikiller]

1 - agree with Chuck, you'll likely need an MSD 8920 tach adapter. The 71-73 factory tach is current driven.

2 - I replaced all the melted diffusers inside my gauges and painted the inside of the housings gloss white. Replaced the bulbs with new incandescents and it's brighter than any Mustang I've owned since 1989.