2wd vs 4wd o.d transmissions

I haven't tried it but I talked to a guy that said all you have to do is unbolt the 4wd section from the rear and bolt on the std. o.d. unit or vice versa to convert a 2wd to a 4wd. We didn't discuss the valve bodies but the 4wd VB might be calibrated different so you may also need to swap to a 2wd VB.