In-line resanators

[VAAKE]

I like some info on in-line resanators, i have a I-5 and it has bad harmonic problem and ends up sounding like a ricer which annoys me to hell.
Any ideas out there who makes good in-line resanators?

Where is the best place to put them, before the muffler or after?

Thanks guy's

[ZR1-S10]

SLP makes reanators called the "Shotguns". Put them before the muffler.