As someone who had a motor need head gaskets and got the MFG to cover the cost of the repair (and rent a car) I can tell you what your going to need.
1. Oil receipts for the CORRECT oil. (yes they checked to see that I ran the correct weight and what type of oil)
2. A log showing the mileage, date and what type of filter you used. (I tear off the end cap of the filter box and write down the date, mileage and what oil used and keep those)
3. MAKE SURE you follow the manual for how often you change the oil. If they say 6 months or 5k miles, DO IT! If they have a lower (severe use) OCI and you fall into that, DO IT! (this is where alot of people get burned!)
My first UOA done showed coolant in the oil @ 61k miles. With the UOA and my log/receipts in hand I got the MFG to cover the $1200 plus rent a car (3 weeks) OUT of warranty. (The car was 3 years old and the warranty was 3yr/36k miles)
Why did they cover it? Detailed records, that I used the correct oil and changed it per their manual and engines show not need head gaskets @ 61k.
Even though I drove 25 thousand miles more than the warranty, they could not tell me that it was "normal" maintenance to replace head gaskets @ 61k.
(Also, I had NEVER taken the car in for ANY 15k, 30k, 45k, 60k maintenance as shown in the manual)
Sadly, this engine ate another set of head gaskets @ 108k and they would not fix it then. They do consider 100k to be the "life" of their motor.
No need to keep old oil filters. No need to have photos. Just records and receipts.
Take care, bill
PS: Also, I buy my oil when on sale and use it when needed. They did not check on WHEN I bought the oil, just that it was correct type and weight.