It is a good guide, but @catzontheloose you can 1v1 Mechs as well it's just best not to do it too close.
Sunflower can destroy it with only half of it's beam and Pea Gatling with a little over half. Husk hop/shuck shock and even a full Corn clip can handle it solo. Citron aiming for the glass and Impeaching as soon as it gets too close to stop it and continue firing is good as well.
As for Chomper as long, as you circle it and try to stay behind it while keeping it gooped you're good. But like I said it's always best to keep your distance, so you prob shouldn't try to take it on solo too much as Chomper.