Sorry about the necropost here but after watching Aliens in 4k, I noticed two things I didn't before.
One is that when Vasquez kills the Alien she pinned with her foot, the leg that actually gets burnt by acid is not the one she is using to pin the creature. I always thought it was that due to the closeness it had to the bullet entries.
When Ripley is threatening the eggs by firing the flamethrower into the air, you can see a gap in the Queen's neck and the mechanical structure inside is visible.