Your screenshot clearly shows you have the patch installed... “shaders patch= active “But I do have the impulse tachometer, at least in these two Mods:
DRM Mod by DRM Modding Team v1.20
1967 GPL Mod by Bazza v2.20
If I recall correctly, the tachometer was a constant sweep when first installed.
I have just been checking other pre-1975 cars including Kunos originals.
Those have a constant sweep, so maybe I'm wrong, and it was built into the Mods?