Stop in for a cup of coffee

I’ll see if I can find the post on FBBO where a guy shared a detailed picture of that from his rebuild. It’s a tech bulletin

There is another dead 904 thread that came up recently. Sounds like fried clutches and time for a rebuild but I want specific references and I don't have access to my books. The simple push-button fault check in the 1969 Motors Manual is a handy way to start...then getting into external pressure checks to chase down the source short of pulling the transmission.