Well, I was just looking at the act from a physical perspective, your character doesn't seem to have lower legs, so presumably if it were perched on top of the Mech I don't really see how it's lower body wouldn't have to dangle downwards. 

'Also just to point out Electro vision is based off the same thing in Alien Vs Predator for hunting the cold blooded Xenomorphs, it works by highlighting the bio-electrics in a creature that can't be hidden unless you effectively 'turn off' as your character can. Point being, mucous does not have any bio-electrics, so it would not impact the lens'