Here is a small tutorial of what you'll need to do to attach the parts, there isn't much, no worries,
For the top main part, you'll see there are two channels under it to make room for the front sight and another prominent detail on the airsoft, The only thing that needs to be removed to attach the part is the back sight as it is to wide to be hidden by the new part.
First thing you need to do is pull the slide backwards, and push the slide lock to maintain it in place while you work on it.
you'll need a phillips screwdriver to remove the screw located under the slide completely in the back:
the back sight will drop when you remove the screw, the small pieces inside are barely holding together with the small spring, be carefull not to move the pistol too much and loose them, try to work with the pistol upside down like shown on the pic to make sure you are not loosing anything.
That screw you removed will be replaced by the similar but longer phillips screw I'm including in the kit, it screws directly into the main part, you'll see a small hole under the part where it goes.
I can't do anything for you to secure the part in the front so I advice you to put double sided tape there or a good glue like E6000 for instance. The adhesive and the small screw in the back will hold the part nicelly.
There is also a 9mm aluminium tube that you can glue inside the barrel of the pistol, it can go all the way in, but it won't be a tight fit as it was hard to adjust to you guys' guns, however, a little bit of glue will hold it fine. This prevents shooting BBs though as the inner diameter is around 6mm, the BBs will get stuck there.
For the V2, you also need to attach the under barrel part, it's not very difficult either,
There is a little set screw holding the flash hidder, you can see a small hole under it, put a small 1.5mm allen key there until you manage to grab the set screw and unscrew it, it might be very tight as it's possibly they used some kind of thread lock.
you need to remove the set screw completely, it's possible it won't fall from the hole, so if that happens, you can just pull the flash hidder and get it inside:
put the flash hidder back in place, put the under barrel part in place fully against the lower body of the pistol, and tighten the very long screw in the empty hole under the new part, using a 2.5mm allen key. That screw will line up with the hole that was used by the set screw, tighten it fully and your part will be held tightly against the pistol and the flash hidder secured again.
Like I explained before, this prevents the slide from moving back, so the V2 pistol is not functional anymore. Just like in the series. I had to modify mine a lot to keep it functional and can't do it for you as it requires to modify the pistol itself. If you want it to be functional and have tools, I can of course answer your questions.
I hope this helps, please ask me if you need any help, it's only 4 or 5 of you guys on this project, so I can help of course

cheers all!