If the design is the same as the 4 inch, most likely, all you'll need to do is put in a 3 in pipe about 12 to 14 inches. The mufflex system has the reducer from 3.5 to 3 already build into the system so you won't have to have anything specially made. Good luck!
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'91 Z-28 5.7, SLP 1 3/4 headers, 4 inch Mufflex/Flowmaster cat back, gutted cats, Edelbrock intake, 8.5mm Jacob wires, MSD Blaster coil, S&W subframe setup, Jacob Pro Street Ignition, Harwood glass hood, Spohn lower control arms, complete Kenwood system, and a few hidden goodies.
IDP.........bring'n it back once again!
Forced Induction 427?..........................on HOLD!!!
Currently have:
Stealth Ram......In polishing phase
Soon to be World Castings 427 sbc
SLP 25lb injectors | 
