It's an Inspector Gadget anime, why should it not have mecha. It'd make a badass intro sequence, picture this:
Gadget walks down to the water cooler, pours himself a glass of water. Just as he's about to drink it the wall behind blows apart and several men walk through the rubble. "Can I help you?" asks Gadget, only to have to have his hat pinned to the wall by a thrown dagger. "Hey, that was my favorite hat." he doesn't get much more time to complain as he's beset by his adversaries, this leads to a fight outside the police station culminating in a fight with a two story robot.
When every thing's taken care of he walks in through the hole and resumes drinking his cup of water, only to spit it out because the cybernetic augmentation won't allow him to drink or eat, so he just sulks back into his office.