there are:
- the four screws at the top edge which you've already identified
- a number of those plastic rivet/push-pin thingys along each side, and along the edge which sits against the bulkhead
- one screw on each drain hose from the HVAC air intake/wiper linkage tunnel
- two brake line retaining clips on the side of the tub which faces the radiator
I think that's it. Then it's just a matter of wiggling it out past the brake m/c and other components. Good luck!
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his: 1985 2M6 SE
mostly stock, but becoming more my creation than GM's with each passing dayhers: 1984 2M4
all stock... with plans for something bigger in the future