66 C10 4x4 Conversion

[VetteC10]

I recently purchased a 66 C10 that appears to have an older 4x4 conversion. In looking at some of the threads it seems there are modifications required to complete this. it looks like a really good conversion, as it really appears to be stock, but it does look like the center hump has been redone with a transfer case shifter through the floor. it also has a later model steering column and a TH350 automatic transmission. Looks to have the original 327.

is there anything I can look at to determine what was done for this swap? I can attach photos if that helps.

Thanks in advance.