I'm trying to find out if it's worth buying a front wing panel (second hand of course) instead of spending more time repairing a rust hole.

I've also got a big dent in a quarter panel (I began calling it a rear wing panel but apparently it's not) which I wouldn't mind replacing as well.

I don't see many quarter panels for sale so I'm wondering if they're really hard to take off or for some other reason, so I'm wasting my time looking for one?

My Focus is a MK1 (1.5 apparently).

you should be able to get 90% of the dent from the rear panel via the boot etc or having it dent pullee. Front wings "new" are not that expensive its the painting after. They all tend to go in the same place so depending on how long you keep the car you'll need to revisit in time.

The rear quarter panel is part of the monocoque chassis on modern cars.  It is not a removeable part.  They have to be cut off with a saw or grinder in order to repair or replace.  The replacements need to be fully welded all the way round.

The front wing is designed to be replaceable, just a couple of screws, much easier to remove & replace those.

Aftermarket manufacturers often make new patten panels to replace the rear quarters, though I'm unsure if they'll still be available for a Mk1 now.  Demand will be very low.  They usually need some fettling to fit right and obviously need to be painted as well.

Rear quarter dents are the worst ones to get on a car unfortunately.

Thanks very much for your replies.

It makes sense now so I won't continue looking for a quarter panel.

In my naivety, I did take off the interior panels some time ago thinking I could push the dent out but there was no internal dent inside so I assumed it's double-walled or whatever it's called.

It is a pain because the dent is right in the middle where the ridged profiling is.

Nothing is easy ☹️

find a puller, vacumn type like they use for carrying glass sheets etc, or the ones shown on car sos and others pin weld keys to the dent then pull out, tho that means grinding the panel back to bare metal.

Thanks, the suction ones are useless for this type of dent because you can't get a seal due to the edged profile.

I had purchased some powerful (apparently) glue sticks a while back after I saw this whacky video of some hardcore Russians who simply blow torched the end of maybe 10 glue sticks together and shoved it on. It worked pretty well.

i bought a cheap kit from Temu but stupidly didnt buy the glue with it, so as yet not tried it they have smaller heads to stick to the body