pulling computer from black case 1992 3.1 mpfi

I'm entertaining the possibility that there's something minor going wrong on the computer board. I'm no stranger to computers. I didn't manage to remove it from the case, removed every screw, the sliding black plastic part, pulled the connectors. It yielded so much resistance when I tried to pull it out. I got it out between 1/4 - 1/2" and was afraid to go any further w/o asking someone. Should I just keep pulling as hard as it is?

I think the microprocessor is made by Bosch. Are the rest of the chips, however many there are, standard off the shelf stuff? If anyone knows. Thanks in advance.

The silver box, the ECM, is just held in the black plastic container by the nuts.....onec removed, should pull out.....

Each computer has a PROM, or chip, that is specific for each vehicle......