I have a very old bike (circa 1996) with broken Shimano Altus 7 speed, hyperglide-c freehub. The freehub is freely rotating in both directions.
I had removed the cassette, but it seems that there is no way the freehub could be removed with allen wrench: there is nothing on the drive side and it seems like torx slots on the other.
Does it make sense to rebuild the free hub without removing from the wheel? Does it make sense to take metal saw to cut part of the thing first and then unscrew the rest?
Update: I am considering this tool to disassemble and fix the freehub without removing it from the wheel.
Another update:
The view from the drive side The view from the other side, the hole diameter is 12mm, it seems like there are some slots there but I am now sure whether I need 10 mm wrench or something else.