Thanks for the input guys.
I don't know what my unit originally came out of. I had heard that spicers were rounded on the top and that the older Brownies were flat topped, like mine. However mine has beveled gears and I had heard that Brownies were spur gear and the newer Spicers were beveled.
I'm familiar with the great tranny website
http://www.6066gmctrucks.org/SM420.htm and would highly recommend a visit.
I'm not sure what the timeline or mechanical difference is between Brownies and the Dana/Spicer Auxiliary trannies. Many of the units have plates that are stamped Brown-Lipe and Spicer.
I've also heard that the newer Dana/Spicer units increased in size with the series. 6000 series is larger than the 5000 series.
My tranny is smaller than a 6000 series that I've seen.
Thanks again
