well i can confirm that '87 944S axles are 25 splines and not interchangeable with VW CVs.
silverbullet, i just came back to this post and saw you had info i am requesting in a different one (i am way to scrambled at the moment
). looks like you have the info i am looking for with the T181 outputs, porsche axles and ali arms. follow-up though:
are the axles 21" (measure CV mounting surface on the output flange to the stub axle)?