I don't understand what you mean by "the replacement was installed before I got this machine". Are you talking about NASCAR still? The coils installed on the garage mechanism are the stock ones.
You didn't clarify which coil it was that you replaced. Was it the 23-800 or the 22-1080 coil?
The old bracket that I included is the one that originally came with the game. The one that is installed is the reinforced bracket. This is the bracket mentioned in SB #160. Check the new one to see if it is bent, but it if isn't leave it installed as it's more robust.
In my experience, if the garage mechanism tries to lift and falls, tries to lift and falls, tries to lift and falls, then it means it is not lifting high enough to engage the lock pin that locks it in the upright position, or the switch for the garage release is not positioned properly, or just bad.
You should be able to test the mechanical sliding, locking of the garage without any power to the mechanism. If it doesn't work when there isn't any power then it won't work at all.
If you are familiar with raising the PF, then raise it up. There are two electrical connectors you will need to disconnect, and then 2 or 3 screws which need to be removed. Removing the garage mechanism out of the PF is pretty painless. It only takes about 10 minutes.
Having the entire thing in your hands is the best way to troubleshoot it.