OK, that's useful information.
It should be possible to do what you want, but there is some hardware and software work required.
That multiple-digit LED display must be driven using multiplexing. If you don't know what that is, Google multiplexed led display drive.
To read the contents of that display, you will need to monitor the eight outputs that drive the segments, and the three outputs that select the digits. (It's possible that the digit selection is done with a 2-bit binary control signal and a decoder, but more likely there are three separate control lines.)
You need to find out how the display driver works, and where you can get access to those signals. Preferably they should be at 5V levels so you can feed them straight into your PIC microcontroller.
Then you need to write code in the PIC to detect when each digit is enabled, read the segment enable signals, decode them into a digit, then combine the three digits into a number that can be used for whatever you want to use it for.
Assuming you can get access to all of the signals at logic levels (so you can connect them directly to the PIC inputs), you could build a fairly small board that might fit inside the meter's case. It would need 13 connections to the meter board:
8x segment enable signals;
3x digit enable signals;
VCC and 0V.
Can you take a photo of the inside of the meter? Both sides of the board would be good. Make sure that IC markings are readable. If necessary, move the display so we can see what's behind it.
Do you understand what I've described so far?
