Leave those power wires alone. Look closely at your picture. I have attached a copy and circled where the power wires have been removed from the board and spliced together thus bypassing the RF filter board altogether. Whoever did it did a nice job of it by using heat shrink tubing over the splices.
This was done from a service bulletin years ago. What happened was the power wiring to/from the RF filter board was burning the connectors causing the gameboard to not operate (game not booted due to no power). I have done this on several Chase HQ and Continental Circuit machines myself. There would be service calls where the board did not power up and there would just be raster on the monitor. You'd wiggle the wires on the RF Filter board and suddenly the game was working again. Naturally, two hours later the location would call back saying, "that game is doing the same thing again....it's out of order". By bypassing the power connections on the filter board, you never have that power up problem again.
As to the "no steering" problem, it's caused by the gas pedal assembly not working properly. Either the microswitch (or wiring to it) is not working or the sector gear is not actuating the microswitch at the correct time. Once the gas pedal is working properly, then the steering will work. I've found the sector gear works out of position on it's shaft.