You were running a 904 in the winter on ice. It never got hot enough to leak lol.

The pump seal alone on your 904 is much smaller and less likely to leak.

Stock glide cases are known for leaking. Bolting bells via pump bolts can make leak problems easier. Adapter plates allow for two distinct possibilities for missaligment. One being surface inperfections and two the dowels themselves. Either can cause leaks.

I ran a solid rear mount and switched to rubber to cut down on the transmission being used for chassis. I read a tech article on the bullit about seeing black on aluminum midplates showing the chassis is flexing causing a solid mounted transmission to bind. This has nothing to do with new bellhousings but, someone else may find this valuable to them.