I don't think its possible to hit the power plant with the CT rules. I think there are only four systems that can be damaged. I could be wrong, haven't gone over this stuff in a year. This could only be in Mayday.
I started to make a whole series of combat charts and maps last year to handle CT (Classic Traveller) space combat.
It would handle everything from ship type, weapons, number of missiles, damage, computer programs, thrust vector and even all the aspects of each missile. Warhead, guidance, propulsion, fuel, thrust and even vector.
I need to get back working on it.
One thing I came up with is using a vector arrow with thrust after playing around with SPI's old CA (Cruiser) rules. Instead of using three different counters to represent present, future and past positions. This I think is also a much better system than Triplanetary's grease pencil marks on a map.