I have an ar-15 a2 will I be able to swap the reciever out into the a3 pistol kit from model 1 sales and if so what else would i need to complete the pistol?  I plan on registering the reciever as a pistol reciever upon completion.

Once a rifle, always a rifle. You have to start with a non-built or pistol marked lower.

The lower receiver is relatively cheap. Just buy a virgin lower (does not have to be specially papered as a "pistol" so long as it was never assembled as a rifle)... plenty of these around for $80 or so on the EE.

Your other option is to file a Form 1/$200 with BATFE to register your existing rifle as a Short Barrelled Rifle, then (once approved) you can slap that shorty upper on your existing lower. This is what I did, as the weapon shoots much better with a stock installed.

Do a little homework first.  This question is answered in painful detail in the above tacked 31 page thread.  I am not trying to be curt but if you read that thread you will have almost every question you can think of about doing a pistol build answered and you won't be asking questions that have been gone over about a hundred times.
As said, if the first build is a rifle it is a rifle and you cannot change it to a pistol no matter what.  Either SBR it for $200 or spend $100 and get a virgin lower for the pistol build.

I apologize for the repeat post but I searched these forums for a few hours and I wasn't finding the specifics only some threads that seemed like they were going to answer my question but then they went off topic and were vague.  Again I apologize for the inconveinence of asking a question, I just wanted a direct answer.  Thanks to the guys who replied, much appreciated.