cutting file .ts accurately

Hi

I need to know how best software or method to identify precisely the cut of the a .ts time to cut with MeGUI.

for example...identifying the frame at the right time that I need to take the program MeGUI make the cut?

I currently use the MPC ts before opening the file to identify the right frame using Ctrl + G, but seems to have a margin of error of a few frames when I put in MeGUI.

there an easier way?

thanks and sorry my engish