You need the special quick-disconnect tool (about $5 at AZ, or whichever store is nearby). There will probably be two tools on the shelf that are listed for Ford applications; one will work on four different connector sizes, the other on two. You need the one that does two sizes (E & F, if I recall correctly).
The tool will slide under the connector to disengage the spring-lock fingers from a flange on the tank pickup line. However, if the connector has been on there for a long time, dirt and grime will build up behind the fingers and prevent the tool from depressing them. In that situation just put a few good blasts of brake or carb cleaner directly into the joint, repeating every few minutes until enough dirt is dislodged for the tool to work.
I had to disconect mine awhile back,it had never been apart before.
Man i fought to get them to release,a small pair of needlenose to just
yank the clips out was a better way for me.Just get new clips at the autoparts store.I had to drop tank again later and they released with the tool no-prob i just think the old rusty clips and dirt packed in there made it impossible.
Hope this saves you from throwing your tools across the garage and loosing them in the wall:lol: