wiring harness help

[slicpartna]

im working on removing my 97 5.7 vortec engine
im going to replace it with a 5.3

need a little help fellas


what size screw is holding the connector for the wiring harness on the driver side?
i can feel something but i cant see it
also how do i remove the beige connector on driver side

i have pried and pulled but no dice

thanks