Thundershot - here is your medium mech:
Medium Mechas: The smallest mecha can go; Medium mechs fill the role support for infantry and special operations troops. While no where near as capable as their larger brethren and unable to mount the battlefield shaking weaponry common to other mecha they are excellent in the reconnaissance and police/ security role.
Medium mecha have the following body slots available: Torso, Back, Shoulders, Left Arm and Right Arm.
Medium mechas add a +4 equipment bonus to a character's Strength score. Depending on materials used Medium mecha have between 50-100 bonus hit points which are added to the character’s total and damaged first.
Medium mechs have a slam attack that deals 1d6 points of damage. They have a reach of 2 meters. Their base speed is 10 meters.
To figure out hit points and cost halve the values in the Large column in Table 2-01 Build Point Cost/ HP on page 37.
Of course this medium mechs aren't really a threat to other mechs (unless you have the Anti-armor Saboteur feat, which I would allow characters in Medium mecha to use), but watch out infantry.