Yes F-5s have been used by USN Top Gun for that job for a long time 
The change now is that the job is increasingly being outsourced to contractors like Tac Air More background info here. The websites say they are ex-Jordanian planes. I understand they are leased not owned, e.g. from the guy I mentioned above, but who knows.
TacAir F5 are not refurbished piecemeal in a shed by a guy and leased onwards but bought outright with approval from State and overhauled at NOC’s factory in Florida. Doubtful a guy in a shed could fix the Tiger’s fatigue cracks issue anyway… but it does make for an entertaining folklore story as always.
T28 wrote:
Doubtful a guy in a shed could fix the Tiger’s fatigue cracks issue anyway
When I was a mechanic in the air force in the mid 80’s we used to train on F-5s, take them apart, put them together again (bits and piece of it). Rather simple and straightforward planes, very easy to maintain. Which is also why they were popular, and still is. Good, robust aircraft that could be maintained everywhere without any special equipment. Perfectly OK for a “guy in a shed”. Even the engines are manageable, small and light compared with the F-16 engine for instance. But, they developed cracks.
We had 108 of them in total. After a certain time, each day the cracks in the wing/fuselage had to be checked, to see if they had grown As time went by, most of them succumbed to cracks. Most of them were gone in early 80s, replaced by F-16. One squadron left, which held it going to 2000. Of those that were left, those 15 were the good ones. They started to sell them in 2000. But for some reasons, the sales never materialized to several different customers until 2015, when they were literally given away
I like measuringworth.com for looking up historic values (I read a lot of old books), and 4,000 pounds no shillings no pence from 1965:
T28 wrote:
TacAir F5 are not refurbished piecemeal in a shed by a guy and leased onwards but bought outright with approval from State and overhauled at NOC’s factory in Florida. Doubtful a guy in a shed could fix the Tiger’s fatigue cracks issue anyway… but it does make for an entertaining folklore story as always.
I know the guy who owns and rebuilt them. He is not in Florida and has a substantial facility, a staff plus network of contractors that do the work, some of whom I also know. What is probably more amazing in terms of “folklore” as you put it is that he made his fortune building rat cages.
You’ll be relieved to know however that the Swiss did have some peripheral involvement so at least something was “done properly” 
They’re not exactly fine examples of photographic art (!) but here’s a couple of screenshots from a cell phone video I took of one of his initial test flights. As I mentioned above, the noise from my POV was spectacular.
Quite a few of the Swiss F5´s are being sold back to the US for this purpose. I think ex SAF airplanes are quite in demand, we also sold all our Hawk trainers to Finland I believe.
At least nice to know they have a life after the air force.
Another F5 photo for those who may be interested (taken today), this one in the ‘before’ state versus the ‘after’ state above…
Wrapped up it is not easy to see where they are from. I would not be surprised if they are former SAF.
I think my guy is more reliable than your guy, Silvaire.
https://www.thedrive.com/the-war-zone/7858/four-f-5e-tiger-iis-can-fit-inside-a-boeing-747
Weird that they were offloaded in Florida and your guy is in California. St. Augustine is a long way by flatbed from Riverdale.
Wrapped up it is not easy to see where they are from. I would not be surprised if they are former SAF.
I would, because we sold them to the Department of the Navy through a Foreign Military Sales contract in August 2002. They were shipped by Hercules to Northrop Grumman in St. Augustine for refurbishing (and some conversions to two-seaters) and put into service with VFC-13 in Fallon, VMFT-401 in Yuma and VFC-111 in Key West.
Another lot of 22 planes will be delivered starting January this year under a similar contract charged to the 2020 budget.
I read that after WW2, Spitfires were available for £30, and a lot of them were scrapped for parts like water pumps which farmers wanted.
