Refurbished G2 Frankenstein (D802 in D800) topic

Hello, resiliently I bought refurbished LG G2 that claimed to be a D802 version.
After a few days I noticed that very often GSM network signal drops with no reason and 3G Internet is very slow eater.

So I decided to update its original KitKat with LGMobile Support Tool to Lollipop in hope, that this will fix my GSM and 3G problems.

After the update phones touchscreen is unusable and it do not read my SIM card, after a quick search I found that this usually happens to refurbished phones because they are not D802. So I disassemble my phone and find out that inside is D800 motherboard.

I found that solution for this is http://forum.xda-developers.com/show...8&postcount=75

So , where can I get stock D802 lollipop and stock D800 kernel?
And can someone provide me with treads about flashing LG's G2?