I have tried to get a definitive list of these theoretical fault codes but could never nail anyone down on them. Yes, I have seen 70007 many times and it was the LSI-11 99% of the time. The only other fault you can be sure of is if you see the ERR LED lit. This means your ERS board is having difficulty. There are some things I would try if I was there:
Are all the fans working? Especially the one beneath the logic boards?
Have you removed each board made sure it was clean and cleaned the edge connector with a SOFT PINK ERASER? Yhen reseated them firmly?
Have you checked the logic voltage? This is very critical. But I check it at the terminal strip just to the right of the logic cards. There are 3 small light blue wires in a row and 3 small lavender wires in a row. The blue and lavender next to each other are the 5VDC. Go out one wire in each direction and you will be measuring the 12VDC. The two outside wires are the negative 12VDC. They are adjusted by the small board in the white logic supply. The potentiometers are multi turn devices and are labeled on the board.