Turkiye can and will upgrade all of its F-16s.
Other than the AESA radar everything is currently ready. The prototype fighter is actively flying and qualified with Özgür modernization package other than the radar. That is said multiple times by the president of the SSB. So why Turkiye asks for viper mod? Because it is political. Turkiye doesn't want to leave the table first when dealing with the US. We know viper deal will be rejected by the congress so Americans will have no excuse to say anything when we move on our own. We will show their double standarst, again, to the whole world and when the time comes we will say dude we did everything we could you guys rejected us not the other way around.
tolgaozbek.com
Turkish modernization is better than the Viper Mod because of its new GaN based radar. APG-83 SABR is not a good radar at all.
This is written by the officers of Hellenic Air Force Academy.
Direct Quote from the Paper.
This is the end result. APG-83 is only slightly better than APG-68(V)9 and loses some performance at some angles.
Aselsan is designing a new cooling system and a new power delivery system for its GaN-based F-16 radar. That means we will push more power to the radar via the more efficient GaN TRM modules. Aselsan radar is expected to have "at least" %50 more range against fighter-sized targets than APG-83. EW resistance is the biggest gain going from APG-68(V)9 to APG-83.