Fix your car's musty smelling AC the right way for under $40

This does not just cover up the odor with fragrances. It will fix the problem at the source.
After a lot of research, I bought the kit below on Amazon for $37. It cleaned an absolutely raunchy smelling AC in my Lexus project car, but only time will tell if it lasts. I'll provide updates in the future.
DWD2 Clean AIR Premium Automotive Foaming AC Evaporator Coil Cleaner (Single 8.oz)
(NOTE: Not a paid promotion. I bought this with my own money)
It requires drilling a small hole in the main duct after your blower, but I feel that this is the only way to do a complete cleaning. The other cleaning methods cannot use foam because they cannot reach the coils without going through a tiny drain tube or spinning blower fan. I think the foam is the key to making this work, as the foam will fill your AC box and coils completely.

[@BaldadonisMike2021]

Thats interesting ..i have a chemical imbalance ..i get vertigo/migraines from chemical pollution ..not as bad from a few yearts ago but i get dizzy if i smell gas/diesel fumes/etc etc ..so does this product have a strong odor? Yeah a update will be great see if it worked after a awhile or does the musky smell come back..thanks for this video my man!

[@aromaticpillow]

I accidentally bought the scented kit, but I could only smell it for a few days. They have an unscented one too. So far, the musty smell has not returned, but there are some other mild odors I need to address. Being a convertible, I think the previous owner might have gotten the inside wet occasionally, so I'm going to do a thorough and deep cleaning of the carpets soon.

[@BaldadonisMike2021]

@@aromaticpillow That sucks..baking soda dumps on the capets ..let sit for a day and vacuum ..helps big time! Thanks for getting back to me..next time i need a a/c to be cleaned I'll try the non scented ..thanks