Hi Kilgon,
I can give some good basic advice here to help make up your mind. Being a auto spray painter since 1976, i have seen personally, many dent pushers as we call them in Australia, push hundreds of dents on every modern day car there is. What has been said above with the guys is true. A top notch dent pusher can perform miracles on a modern day dented panel. (depending on how badly the paint is damaged) The thin steel used today assists the pusher in massaging the dents out successfully.
That said, i have so far, not been a witness to any pushers that have pushed old thicker panel steel prior to 1978 vintage. As said above already, if you can find a good dent pusher around your area(believe me, there are really good ones and very average ones out there), that is willing to take on the older steel, then that's good. Many won't. I have found them locally where i live. I have been considering using a dent pusher to remove a few small dents in my '73 Vert for some time now. Trouble is, that they don't come cheap. Most pushers quote to push one dent only, the most expensive cost, and the more dents they push for you, the more the price comes down per dent. I was quoted around $150.00 AU for one dent. He was to come out to me. If you drive out to their workshops, the pricing comes in cheaper. If a pusher can push a dent and save the paint as well, then that's a win/win situation all 'round, as you will not need to refinish the panel or panels needed to be resprayed. That's a good cost saving, and cheaper than having to panel beat the dent and refinish the panels. It all falls apart if the pusher wins the dent push, but can't save the paint finish. Then, you're back to square one with having to refinish your panels again.
OK, lets talk about the paint side of things. First up, when a modern day car gets a dent in a panel, the key issue is whether the paint film has been damaged as well. This will depend on what type of object the panel was struck with. A dull soft striking object should not damage the paint film in most cases. Sharper or rougher objects tend to damage the film. Paint damage with dents, comes in many degrees. Depending on how severe the paint damage is, depends on whether the paint film can be rectified or not. The sad thing is today, most car manufacturers don't put a decent amount of topcoat paint on their cars, be it clear coat or solid color. So if the blemished paint has not been damaged too badly, and can be cut and polished, or even lightly sanded with a very fine wet & dry paper first, you will be lucky, and you will win the dent push job. If the blemished paint has been scratched badly, where the contact object has penetrated the clear coat, gone into the base coat, then it's game over, as the damaged paint film can't be rectified properly, and will need to be refinished.
In regards the paint film cracking ......................................... This problem has several variables to consider. You mention above that your car has had a respray not long ago in 2019. In that case, that basically is a good advantage. However, it is important to take into account, what paint procedures were done to your car. For example, was the old paint removed back to bare steel or not. If so, was there any bondo used in that now dented area or not. How much primer/putty film build was used over the bare steel. Basically, it goes that the more primer/ putty and top coat build up you have on that steel panel, will play a vital part as to whether the total paint film will end up cracking or not. It comes down to the degree or level of the paint build's flexibility factor.
What is worse, is the other senario where your painter painted over old paint. If so, we will assume the old paint was in good condition. But in terms of film build thickness, how much paint film build did he spray over with the fresh new paint? That's the important thing, as again, the thicker the paint film builds are, the more chance of the paint cracking. So the equasion is - the thicker the paint film build is and the older the film is and the deeper the dent is will all play a part in the paint film cracking on you or not. It comes down to the paint film builds ability to flex (shrink and expand) and move with the steel being pushed back out again. If your painter has a micrometer, then he can take a paint film thickness reading around the dent area to determine what paint film thickness you have. Paint film thickness is measured in microns. As to your outcome, he can advise you if he feels that you have too much paint over the bare steel substrate or not. You can then make a better educated guess as to the possibility of a paint cracking issue occurring or not.
Based on what i have said above, you can now make a better calculated guess, as to the likely hood of your paint cracking on you. But remember, at the end of the day, paint film cracking is always a gamble no matter what. There are NO certain outcomes here. In my opinion, if your painter painted over bare steel, and did not use Bondo, and did not apply heavy coats of primer/putty, and did not apply more than three coats of clear coat, and the dent was a small diameter and shallow, then i would be very surprised if the paint film ended up cracking. Outside of that description, then you would increase the odds of cracking taking place. At the end of the day, you are the only one that can make that call as to whether to push the dent or not, because no one say say with 100% certainty that your paint will crack or not. It's like being in a damned if i do/ damned if i don't situation. Hope all that helps.
Greg.
