How to Disconnect Trans Cooler Lines

95 3/4 Ton Conversion Van.
Has factory Auxiliary (External) Tranny Cooler in front of Radiator. The hard lines from it route downward under rad. At that point, they have connections to the standard steel lines. Some type of quick-connect, the side on the cooler lines has a large hex, (approx 13/16). The mating connectors (what little I can see of them) look like a thin flat disk, up against the hex of the cooler line fitting. I can see a small gap between the 2, and it looks like a spring clip in there, (like the type that you find holding a window crank handle onto the door of an older car).
How do I disconnect them? Several tools at parts store, universal types, most look like they surround the line with a small split sleeve, which would slide into the connectors. There is no hollow or opening on these connectors, they look just like a solid round disk on the end of the cooler lines. (Plus whatever part of them is inside the mating cooler line connectors). Thanks in advance for any help or advice, -Jim.

On my 90, you squeeze the 2 taps, push the line in then pull it out. No special tools are needed.

//2000CAYukon

Yeah- the clips remind me of the window crank handle spring clips- the same ones are on the radiator coolers of all U-vans- (Venture etc) I use a dental pick hook tool (purchased as a packing hook tool at most tool stores) and get in under the back side and gently wiggle it out- so as not to lose it (they are $5 from the GM dealer) - the to re-install, you put the clip in place and snap the line in-- this is a factory convenience quick connect method- I suppose there is a tool- similar to the window crank tool- but I have never used it- and have probably disconnected 30 or more in the past 6 yrs....

small pick or flat screwdriver then grab the flat part of the clip with a pair of needle nose pliers and pull it out.