What can be used use to thin T-Cut?

[Pastor Of Muppets]

I've got a couple of the large plastic bottles of it but they have been sitting a while and have turned thick and gloopy, I've taken some small amounts and tried mixing with white spirit / petrol ! / glass cleaner etc but none of those have worked, ends up even thicker and looking curdled / congealed. Any ideas folks ?

[DVandrews]

I’ve thinned it with water before..

Dave