David said 100K, so since he lives in Canada, I assume that means 100 KmPH. At 3000rpm, that sounds a little low for 3000rpm even with a 3.54 diif, but not very far off. 3000rpm with a 3.54 diff should be about 65mph or 105KmPH. Now, with Joey's car doing 100MPH at "a little over 3 grand on the tach", he must be using a 2.5:1 diff, or his tach reading is way low! With a 3.07 diff (isn't this what you have, Joey?), it should be spinning 3877rpm at 100mph. Looks like the speedo or tach needs a serious recalibration. By the way, all these numbers are in the Service Manual on page A.5. If you're tyres are not the original size, and the speedo hasn't been recalibrated, your numbers will vary somewhat.
-David