I've tossed up info on headers and installs in the past, and it never seems to get old. Here ya go.
SLP's/SD's: Very easy to install, the slip fit is great. Ensure if you have the SD's that you plan for the O2 hitting the side of the tunnel/firewall and you pick up the band like torca clamps. FWIW I love to do the installs on these two types of headers.
Togs: Installers nightmare of headers. At least the ones I've done. The flange for the crossover to rear header is right at the trans dipstick. You have to bend the tube, then have three people on hand. One on top, another on bottom of the flange and a third to get the beers. IMO having the donut and flanges is bad, they are in the exhaust stream, a slip fit is nice flow IMO.
WB/ZZP: honestly they look basically the same for shape to me. Overall an easy install like SD/SLP's without surprises. However the ZZP EGR relocation is a bit unnerving. You must bend that EGR tube a good amount and those tubes crack just being bolted to the LIM. Bending is not my favorite part. Otherwise.. good install.
