I picked up a nice co-branded Birks Eterna-Matic 1000. The watch was gaining 6 minutes a day. I put it on the timing machine and the beat error was between 5.6 and 6 in various positions. The amplitude was good in all potions. I put the watch in beat (between 0.8 and 1.0 in positions) but the movement was still very fast. I tried to regulate the rate using the gross regulation but the best I could do was +3 minutes per day. Looking at the hairspring with a stronger loupe I saw that there are two index pins and the boot. The spring is between the second pin and the boot and I'm thinking the spring should be between the two pins. I just want to double check this before I remove the balance and place the spring between the pins.