gutting out my stock h-pipe

[Shotgun28]

1) Has anyone done this?

2) What is involved?

3) Any performance gains from stock?

4) Will a check engine code register?

5) Finally, do I have to reinstall my smog pump assembly?

Thank you in response, partial answers are welcome as well.


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91 LX Convertible Gray on Red B&M Shift improver kit,ASP red alum. underdrive pulleys, Richmond 3.73 gears, 1 5/8 Flowtech long tube Headers and off road h-pipe, Flowmaster 2-chamber cat-back with S.S exhaust, MSD 6A Ignition with coil,Cap and rotor, Taylor Pro wires, K&N 12" conical filter system, Jet stage 2 performance chip,GT40 P heads, looking at new exhaust, Lentech Street Terminator plus.