How to reinstall speedometer needle

[matrophy]

Removed gauge cluster to replace bulbs and install a stock tach I was walking to the workbench, I dropped the cluster and caught it in mid air but broke off a small piece of the speedometer needle where it plugs over the shaft. I was able to glue it back together but after I replaced the needle on the speedo, I took it for a drive and was reading 15 mph when stopped at a stoplight. I removed the cluster again and  rotated the needle to the left so it was on zero. It was at zero when I pulled out of the driveway but when I reached the first stoplight, it was reading 8-10 mph when stopped. Since I am nervous about breaking off the little part of the needle again, I have been reluctant to do a lot of wiggling or pushing of the needle and I am wondering if I am missing a detent on the needle that lines up on the shaft in only one position or if there is some other trick to set it when disassembled. I had the cable disconnected from the tranny in order to remove the cluster and I also added a stock tach to the cluster and I mention this in case any of these might affect the speedometer