HELP! output shaft fell out... OUCH

[warpspd]

I am in the process of pulling the engine/transmission and once I pulled the cv off the driver side BAM the bolt that holds the
output shaft fell right on my head and the output shaft just
slides right out now. The bolt must have been loose for a while as
the threads looks messed up. Once I had the tranny out of the car and seperated from the engine I took the bolt out of the other side and tried to use it but the threads on whatever it bolts
into are I guess messed up too. What next?

Do I pull the thing apart and start rebuilding it. If so What exactly do I have to replace?

[warpspd]

Here are a couple more pics but not very good ones.