A-904 - Five Clutches, Anyone Done that?

I do not believe that the 5 clutch drum from the A999 will fit the 904, I recall we were going to use one in my 904 when we did the low gears swap, but the drum is physicly larger in diameter, I could be mistaken, we did have 4 trannsmissions tore apart at the same time that we were mix and matching parts from, but I am pretty sure thats what it was. As stated though you can have a new c clip/spring clip groove machined in (if your drum has the room for it) to allow you to stack another clutch in there.