re: Blowing in insulation: how difficult? And how much would it suck in June?

Repair done. I bought some flashing material and cut it to size. Siliconed the edges of the patch sheet then put it over the hole. Then o screwed the hell out of the edges with small self-tapping screws. For good measure I put a TON of foil tape over the whole thing in an alternating pattern, multiple times. I also went around the whole unit to feel if I felt any other leaks. I found a joint where there was a small amount of leakage. I taped that up as well.

My wife kicked on the A/C while I was finishing up in attic. The temperature is falling in the living room now and we can feel the air flow finally. Looks like this was my major issue.

I do still need some insulation. But at least I’ll be able to wait until a better time of year.