[blucar]

As you can figure out from the above comments.. Retaining the stock '36 spindles can be done, however, it is a lot of extra work to accomplish very little.
It is much easier to convert the mechanical brakes to hydraulic using a '41 and later spindle/king pins... This gets rid of all of the mechanical brake parts. Use '42-48 backing plates/brakes with '38-39 drums and your stock '36 wheels. The peddle assembly can be a stock '39 unit and/or something from one of the aftermarket vendors.
The '42-48 brakes will give you better stopping and the parts are readily available from parts vendors..
I try to follow the KISS theory... Keep It Simple Stupid...