833OD into 78 D100 questions

2 wheel drive trucks with the OD use the same floor pan as the 3-speed manual or auto.
I have the factory plastic shifter mount for the floor with a boot that is correct for your truck, transmission.
The flywheel will be a 122 tooth for the bellhousing. I don't think your current flywheel will work but check the tooth count to be sure.
I have all of these parts for sale cheap, pm me.