Merging Two ISO installer files of Mass Effect 3 PC Game

I have so many attempts to combined games installer from several cd’s into 1 dvd or a single file installer but I always got failed. The logic of combining those multiple installers is to save CDs and a hassle free installation. This time I make I work on a Mass Effect 3 game installer though I don’t think it will go the same on other games but it will give you basic idea.
Back to Mass Effect 3, more or less its 15GB file size and usually split-up into two ISO files. Our goal here is to combine the two ISO files to become a single installer that can be burned a DVD (Dual-Layer DVD preferably and it must be compressed well, ask me if you need help)

1. First, you will need an ISO extractor software. Download PowerISO here.

2. Extract each ISO files in  a separate folders.

3. When you’re done extracting,  open the folder GAME and you will see as screenshots below:
4. As you can see the game files start from GameFile.part01.exe up to ….part35.Now  open the second ISO file that you have extracted and find the GAME folder, in that folder you will see the  GameFile.part36.exe to …part56, copy and paste it to the first GAME folder.

5. Now, delete the second folder to save space. If you want create a single ISO installer drag all the files you have combined into the PowerISO window and make ISO file.

6. Try installing, it will run without an error ( be sure your pc  have the minimum 
requirements for Mass Effect 3). You’re done. Congrats!