Go to the mechanist and try to buy the Carro. If you are lucky, you will get a cheap SV with an OC generator. This was only tried on the Liberties server, but it might work on other servers. After you buy a Carro, go to Edgeworks and set the legs to Heavy 4, body to Heavy 1, and whatever your weapons are (if you replaced your Carro's weapons) to Heavy 1. If you do not have enough money, fight in Free or D rank a few times to pump it up. Go to Hard-Wired after you are done upgrading. You will meet with JJ and DD. After the sequence, depending if you are on a D rank day or not, you can fight. However, it is recommended to skip a few days ahead and go to a Free fight day. Once there, you can get over 50,000 in C credits alone, but only if you can survive long enough to steal all credit crates at the helipads (giant glowing "H"s). After getting your first win, go back to upgrading your unit's Armor value at the Edgeworks. If you have already done that, go to the Chip shop and buy a WOLF Chip. Any Chip is fine, but Wolf 2 seems to be the best for the Carro. Then, buy the OC TB if you do not have it. Skip a few days ahead to one of the D rank rumbles and enter it. Your unit should be so powerful, most of them should not stand a chance. However, be careful. A lot of units like to get behind you, but are too dumb to actually accomplish it at this rank.