Advanced adapters has a great tech section that will answer all your questions. There are two 205, figure eight, and round, switch was 1985. Also ford used 205 and so did dodge. Internals are the same, so if necessary, you could change the transfer case input shaft. The 400 trans is 32 spline output, 465 has 10 spline input, and believe 27 output, same as a TH350. Was the 465 out of a chevy? Bottom line: 1) TH400 needs to adapt to the transfer case. Do you have the adapter? this will bolt to the trans after the tail shaft extension is removed.
2) The 400 32 spline output shaft will then be inside the adapter, which will in turn bolt to the 205. It is driven by a female (ID) coupler, 32 spline on the trans output end, and must mate with the input on the transfer case, which in your case will be a 10 spline. At the minimum you will need the sleeve, and GM only made 10, and 27. If a sleeve is not available, you will need the transfer 32 spline input.
Here are a few pics:
1) TH400 (car tail shaft still attached), 32 spline
2) id view of transfer case 32 spline adapter.
3) Advanced adapters 32 spline input shaft for 205, big front bearing.
4) As a note, this is part of a kit I bought to adapt my 454/4l80E to my 205, as th400 and 4l80E are similar, and have the same output shaft spline/OD.
A1. Full Size Truck Transfer Cases
www.advanceadapters.com
Hope this helps Kurt!