You have to pull the instrument cluster at some point. I usually undo the hex socket head bolts around the perimeter of the instrument cluster, three on top, two on bottom I think, then undo that cable connect in the scuttle and you can push the cluster forward via the cable end and wiggle the cluster forward enough to reach back there and undo the end on the speedo, it is either another compression sleeve style or it's a but thumbscrew type, you'll want to know anyway as the replacement cable you order needs to match the back of your speedo, there's two different style connections (compression sleeve and thumbscrew) I don't know when they switched them around. You don't have undo the three wiring connections but it's not too hard to reach back there and tease them off, you can get the cluster out from behind the steering wheel but some will just pull the wheel off (if it comes off easy, mine won't budge so I've never taken it off).
Only thing left connecting cluster to car is a yellow/orange wire that runs to the exhaust gas sensor reminder light, cut it. You can hook it back up if you want but I wouldn't bother, that idiot light is annoying.