Electrical Connectors disconnect '08 XC70

[Faust]

I have been attempting to replace my alternator. The stopping point is removing the intake manifold, which has five wires running into it for sensors. Without being quite sure how I did it, I have disconnected two wire(s) at their connectors. The remining three simply will not budge.
I understand there is a tab which must be depressed in order to separate the connector. I have tried that to the extent my fingers will permit, without luck. If I try squeezing it here and there with small pliers, am I likely to do any harm?

[Krons]

I tend to go with a flat screwdriver to press/pull tabs on connectors. A pick if it is a really small connector where a screwdriver won’t work.

[Faust]

I would appreciate being pointed to a video, or even a still photo which would show the locking system on these connectors. I figured this for a four hour driveway job; this is the end of my second day, and I haven't even got the intake manifold off. I just succeeded in getting connector 4 off with the aid of a pair of tubing pliers, a tool I had forgotten I owned. Now I am down to the bottom connector which has to be reached from below, I am dreading that. All of the intake manifold videos I have seen simply say remove the electrical connectors, as though it was nothing. This not my first auto repair job.

[Faust]

I am still hoping for a hint of any sort here. I am down to the bottom connector (all instructions say most easily reached from the bottom; I have been reaching down there for 1/2 an hour); I have just spent an hour with every type of puller and squeezer I own hoping for a Eureka moment. These connectors have previously discouraged me from working on my Volvos.

[abscate]

Faust try this. Press the connector together tighter, while you compress the latch. I find the latch is often under tension from the seals