Yeah, no worries.
I (and everyone else, it seems) reckon on the extra HP and shields making the overhaul worth it for 2. I hope the penny doesn’t notice the flotilla that’ll be trailing it.
Don’t buy FP for Mission 2, though. Even if it’s the best deal, it won’t help ya. Better to buy anything else.
If you aren’t confident you can buff enough, how about Mission 3? Overhaul, 5 drones, you’re pretty much guaranteed to come out the other side with b1000, whatever happens. Or upgrade a bit, try 6 or 7, but then it gets a bit riskier.