Reddit mentions of Kaisi 16-Piece Precision Screwdriver Set Repair Tool Kit Compatible Samsung, iPhone, iPad, Computers, Laptops and Other Devices

Repairing the old kindle is an option, if you are so inclined. A replacement screen, a simple tool kit, and about 30 min of your time is all it takes.

I got mine from here http://www.fixez.com/store/lg/lg-nexus-4/lg-nexus-4-e960-battery-replacement. They were a little bit pricier then some of the guys on ebay, but the battery that I got from them seems to be the same one that was originally in my phone. If you don't have the tools need to remove the torx screws and such I bought this pretty cheap set of them of Amazon that worked http://www.amazon.com/gp/product/B00E3CHLLC/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1.

https://www.amazon.com/gp/product/B01A0EXE44/ref=oh_aui_detailpage_o05_s00?ie=UTF8&psc=1

This will help with opening it up.
https://www.amazon.com/Kaisi-Precision-Screwdriver-16-Piece/dp/B00E3CHLLC/ref=pd_bxgy_147_2?_encoding=UTF8&pd_rd_i=B00E3CHLLC&pd_rd_r=5HGZ0SEW8RGY75FNQXVF&pd_rd_w=hSlxs&pd_rd_wg=aj4MU&psc=1&refRID=5HGZ0SEW8RGY75FNQXVF

After my own extensive R&D, I've come up with this. Give me a dollar.

Edit: Or try this. It's less than $7 and even comes with a Torx screwdriver if you need to take your Pax apart.

https://www.amazon.com/Kaisi-Precision-Screwdriver-16-Piece/dp/B00E3CHLLC/ref=sr_1_15?ie=UTF8&qid=1505171804&sr=8-15&keywords=precision+tool+kit

Blow out the fan with some canned air (you have access to the vents on the left side of the case) and see if that makes an improvement. If you're absolutely dead set on having the thermal paste replaced, take a stab at it. As long as you pay attention to which screws went where, you'll be fine. Take pics as you disassemble it so you have a record of what goes where.

You may need a spudger or guitar pick tool to help ease the case open. I have this set of tools (non-referral link), they're thoroughly useful for taking things apart.

You'll need to clean off the old thermal paste - 90% rubbing alcohol and a q-tip will do this nicely assuming it's actually thermal paste on there and not that grey rubbery crap, in which case you'll need a razor blade and patience.

Thermal paste is cheap to acquire, either the Cooler Master or Arctic Silver should do fine.

I mentioned it as a possible solution on the onset, and he offered it up as a solution as soon as he saw the issue. It's cheaper for Dell to ship a card vs getting a whole computer back and replacing it themselves.

And no, you need to buy the screwdriver (I bought this on Amazon).

Replacing the screen assembly is fairly easy and not horribly expensive if you're any good with a spudger and a screwdriver.

I bought [this] (http://www.amazon.com/gp/product/B00HKL3DEM/ref=oh_aui_detailpage_o07_s00?ie=UTF8&psc=1) from Amazon and used [these] (http://www.amazon.com/gp/product/B00E3CHLLC/ref=oh_aui_detailpage_o07_s00?ie=UTF8&psc=1) tools to install it following [this] (https://www.ifixit.com/Teardown/Nexus+5+Teardown/19016) iFixit teardown. Took about 20 minutes.

How's this?
https://www.amazon.com/Kaisi-Precision-Screwdriver-16-Piece/dp/B00E3CHLLC/ref=pd_bxgy_469_3?ie=UTF8&psc=1&refRID=DHE8F8X8BZR4P9JF20P9

https://www.amazon.com/Kaisi-Precision-Screwdriver-16-Piece/dp/B00E3CHLLC

I bought something like this to take the phone apart. It is a very easy process to get to the camera module. I'm not sure how you would go about cleaning it. I'd assume you just have some dust on the inside part of the phone (not inside the module?). Google an ifixit article and give it a shot! The Nexus 5 was the first phone I ever took apart and it was very simple.

(I had to remove my camera modules - front and back - due to security at my job). Good luck!