Long story short here....even if you got the internal bolts out you will have another issue with top of trans shift housing hitting the cab floor.
Sounds counter intuitive but its easier to pull the engine and trans out as a unit, then disassemble the bell housing/trans from the engine...then the bell housing from the trans.
Suggestions....
Replace all engine mounts while you are doing the job, two on engine, two under bell housing to cross member.
Replace the clutch kit including new pilot bushing.
Make sure clutch release bearing height is same as original one fitted.
Make sure Z link is in good condition and fully lubed on pivot points while you have it apart.
