You *MIGHT* have saved some time by using the Fortec ChEditor program. It is a REALLY POOR program, however it WILL allow you to add, delete and edit channels and transponders.
What I would have done, is before doing the factory reset, use the channel editor to save your sats and channels, and also before doing the reset, there is a similar option whereby you can save and recover via your remote on the receiver. In case the ChEditor route doesn't work right, I'd recommend backing up your channels via the remote before doing the reset, then you can just do a recover to get back to where you were before, if things go wrong.
IF you are using USALS, you can use the ChEditor program to save your sats and channels. Then you sit down at the computer, and remove all the unwanted sats, transponders, and channels that you don't want, and you can add manual channels, etc. Get the thing set up just how you want it. Then load that data into your receiver, and you're all set. However, if you're using DiseqC-1.2, there are problems with this.
If you're using DiseqC-1.2, there is a problem, and that is that you won't be able to remove any satellites or the
Mercury will forget where on the motor it saved their positions. So, if you intend to use DiseqC-1.2, make sure that you don't delete any satellites, either with the remote or via the ChEditor program.
But either way, even though this is a poor excuse for a channel editor program, even compared to the program that the have for the older Lifetime receivers, it is still the easiest way to clear out unwanted transponders and channels, and/or edit most (not all) of the parameters for the channels.