I just failed handgun and patrol rifle instructor training!! I couldn't qualify. I am a firearms guy.
I had a 4 power scope on AR15 ( 48 yrd.shooting and under). I had on huge electronics ear protection,
I had no AR15 mag pouches for tac vest ,put mags in pockets. Glock mags in snap pouch and velcro pouch. We shot walking, prone and kneeling. My eye protection fogged up. Plus it was 93 degrees  ,in the sun with a heavy tac vest on. Please give me advice on proper mag pouches and location on vest. Ear and eye protection. Anything that will help me improve greatly. I  shot a score of 72, min. to qualify 80. I  know practice,  five years ago, I  shot 100 on everything  every time. What about optics on my Glock? I  know this is long  ,but I  know you guys will give me directions. If I'm putting this in wrong forum, let me know.
Thanks. BravoCharlie

It is hot right now and that never helps.  Running to the 400 yard line and shooting on a line with other soldiers for time when your eyepro fogs up always sucked for me.  I've found finding the right eyepro that won't fog is always a HUGE help.  Minimalist eyepro with anti-fog protection works best for me.

These are the eyepro I wear on a sunny day:
KleenGuard 22475 Nemesis Safety Glasses Black Frame and Smoke Anti-fog Lenses For Outdoor

Under a helmet I always just wore earplugs.  Gave me maximum ease of getting a proper cheekweld in various positions.  There are slim electronic ears out there that decently with a rifle.
I spend enough time on the range these days to have finally dropped money on Sordin Supreme PRO X

There are lots of choices for open top kydex belt mag carriers that will give you speed during reloads.  If those are an option for your quals I would try that.  Otherwise practice a lot with the method of carry you have.  One of my students did a ton of practice carrying his spare mag in his pocket and completely shocked all his contemporaries with his fast reloads.

What the Master class folks do is get all their range day gear on and practice dry.  Work all the positions and stages.  First for accuracy, then add a timer and go for time.   There are no substitutes for proper repetitions.  Perfect practice makes perfect.  Recency is a thing.  Make sure you go into the next qualification warm.  At a minimum dryfire everything before you do the qual.  My students usually run everything with airsoft first.  When they can do that for time and accuracy, we switch to dryfire.  When they do dryfire properly we start using live ammo and things tend to come together expending minimal ammunition.

I would avoid optics on your Glock until you get lots of practice with those.  Finding the dot can be slow and frustrating until you have enough reps.  I'm told 9,000 reps is the number on that.

4x magnification on under 50 yard shooting is almost certainly holding you back.  Romeo5's are cheap and effective.  EOTechs are even faster.