Any on the power clip should definitely be removed.
For locos, if it works with the capacitors present then leave them, otherwise remove them. Some decoders are more sensitive to the presence of capacitors than others. However it is easier just to cut them all off regardless.
For locos, if it works with the capacitors present then leave them, otherwise remove them. Some decoders are more sensitive to the presence of capacitors than others. However it is easier just to cut them all off regardless.