D7 3T clutch links Thermoids

Friend of mine has a 3T and can't get the retainer for the clutch links loose to replace a broken one. He has had another 3T which had cotter pins and flat washers holding the thermoid link on and replaced plenty of them on that tractor.

According to him, this tractor has some different sort of retainer that holds one or both ends of the thermoids in place and he cannot get it loose. He describes it as sort of a latch mechanism which must be flipped up and then the pin removed, but he says the pin won't come out. He thinks it needs to go out forward toward the engine, but there's no room. Did someone assemble this clutch out of the machine and put things in backwards?

Wasn't there something about reversing the clutch plate on the D8 so that the flywheel pushes the clutch instead of pulling it? Maybe this is the problem?

I only have a Serviceman's Reference book for the D6 to refer to, so if someone has a D7 3T book and could refer to it, maybe I can pass the information along.

I don't see anything different in the parts book, just the usual bolts, nuts and cotterpins, with nuts and cotterpins on the flywheel side which should be well out from the flywheel.
The pusher links were on the D8-2U only.