[Tom Goldman]

I recently refurbished an old Modified 67 Nova with a Dana and changed it to a 9".
Same width housings ,solid 35 spline axles ,same brakes.
Dana was a passenger car housing ,not a truck housing with the heavier webbing, had .195" cm tubes and a Summers Bros. spool ,[heavy!]
9" ,Strange iron center, Strange steel spool ,Chassis engineering mild steel fab housing with back brace, all the same brackets as the Dana , total weight difference ,a whopping 16 pounds.
If you used all the same light weight components in either rear , the difference might be around 22 pounds, due to the additional savings from a 9" aluminum center.

My opinion is if you are building a new car , a SS car that changes ratios often or a car that needs a ratio not offered for a Dana ,then by all means build it with a 9" ,if not leave the Dana in.
If your heavy wall tubes are bent ,have them replaced with CM .195 tubes ,for a fraction of the cost of changing to the 9"
There are a whole lot of competitive race cars out there with Dana's in them !