In my Blazer I have power everything, so I have a question. If I get an OEM Keyless entry can I get it to work with my truck if it's all power? Like power windows, locks, yada yada.

 

yea i had it with mine....shouldn't be a problem

 

You may already have the RKE (Remote Keyless Entry) module installed. It should be located above the DLC (Data Link Connector). If you have RPO code AU0 (A U Zero), then you already have the RKE module and a previous owner must have lost the remotes (check inside the glove box). If you do not have RPO AU0, then look around in the junkyards for a blazer with it, and pull the RKE module and possibly 1-2 ft of wire after the electrical connection to the RKE module. I believe that if you have power locks, the RKE wiring is there, but I have been wrong before.

Here are two threads on this subject (search function works...):
keyless entry fob
Adding Keyless Entry

Good luck and let us know if you need any more information.