Should I treat the beginning of frame rust?

The frame on my 2012 Tacoma is starting to rust. Not bad.. But on the corners and welds rust is popping through the paint, and the leaf springs are bad.
I ordered rust converter and paint and wire brushes for my angle grinder. Then spent a couple weeks reading about treating rust.
Today I went out to get started, and after spending a couple weeks looking at rusty frame photos online, mine now seems like nothing.

I am wondering... Finding sparse, mixed info when searching...
Will Ospho or similar rust converter products damage the good paint? Most of what I read seems to imply it will get under and cause the questionable paint to come off. But will likely leave the good paint alone. My frame is definitely more good than bad.
I am wondering if it is safe to spray the entire frame w/ rust converter and maybe convert the rust that is popping through into black rust to slow that down. Then I'd spray paint the particularly bad areas, too. Or if I might do more damage than just leaving it alone. I don't really want to do a full frame, strip it down and completely repaint it type job. It's not that bad.

 

I am not saying my way is the right way but I did it this way.

cleaned the rust with wire brush/scotchbrite
Painted it with primer and paint
Fluid Film everything once a year (I am not using my truck in the winter, otherwise would fluid film twice a year)

also once there is rust it will grow faster, so when you find/treat it early it makes things easier ...don’t wait

 

Yeah, i guess it's the converter that is causing me problems.. Well, not problems but confusion.
I like the idea of converting it before painting, as for a really bad rusty frame, that is the solution. But maybe for this light spot rust, it makes more sense to simply mechanically clean it and paint it..
It's just easier to spray some acid on it, than scrub it w/ a pad . And I feel it's more thorough, as it will soak in behind places I can't reach w/ a brush. But I'm concerned w/ making the existing good paint worse.

My steel wheels are in a similar condition.. Smooth red rust just barely starting to show through the black paint.

 

One has to remember that as good as Fluid Film (or similar products) are, they're much more effective over a properly prepared and painted surface than they are over bare metal. Get my drift?

 

Use the rust converter only on the areas you have brushed or sanded. It has no conversion effect on paint.

Then prime and paint those areas.

Then use a protectant like FluidFilm on the entire frame.

Basically, you are repairing rust damage first, then protecting.