I've asked this question before but I'm hoping for a few more responses as I'm still "in the dark" as to what to do. Thanks to those who responded earlier, but please read on...

Background: The speedometer in my 81 242 is reading inaccurately. This is a US car that has had a Canadian B23E and the 4 spd + OD transmission that was attached to that engine installed about 3 years ago. Since then I've had an inaccurate speedometer. I'm not sure if it was reading accurately before that. Additionally, I recently had to replace the headlight switch in the dash and like an idiot forgot to disconnect the battery. Luckily, the only thing I shorted out were the lights that illuminate the instrument cluster at night, so I can't see how fast I'm going in the dark. So, I've got to replace the instrument cluster. This is the 85 MPH, clock-on-the-left instrument cluster, and has r0,980 at the bottom of the speedometer.

Here's my ultimate goal: I want to replace the existing instrument cluster with one that has the 120 MPH speedometer (of the correct ratio, of course) and the large tachometer to the left. How do I make sure I'm getting the right one?

Thanks,

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1981 242DL B23E 268K mi.