I've removed my share of round gauge clusters...but, only a couple of square ones over the years. I'm assuming the bezel is off? Don't remember if the square cluster has these, but I'm sure it must as these are what further holds the round gauge housing to the dash. But, there is a 3/8" recessed nut on either side of the large round gauges that need to come off. What I notice most often is the dash has swelled a little bit from age around the opening and the cluster housing gets hung up and requires a little persuasion to clear the lip. The speedo cable doesn't necessarily have to be completely removed prior to pulling out the cluster housing. However, the retaining clip should be released so the cable will slide out of the speedo as the cluster is pulled forward. I also lower the strg column to gain more room when bringing the cluster housing forward (don't forget to remove the shift indicator cable from the strg column before doing this).