Type S axles are needed because the outboard splines are larger. Check the dealer to see if parts like the Half Shaft (#18) interchange.
Again, check with the dealer for the exact parts required and the interchangeability of all these parts. I put this swap guide together on the basis of using the Type S parts I acquired, so I can't be 100% sure about the fitment of the Base model parts or the piecing together of other RSX and Si parts. :)
http://www.we-todd-did-racing.com/we...MXk1NDE%3D.jpg