I'm in the process of building a pretty serious A20 for my vintage accord, I'm hoping I can get a real answer on this here, and not some of the idiot answers on the main board. I was lucky enough to source an S&S header for this motor, not long before they closed up shop, this led to a pretty extensive project of building a full custom stainless exhaust all the way to the back, the header comes in two pieces, mainly for shipping,as it's a long tube, originally it had bolts and washers to hold the two pieces together, instead of the header being able to come apart, would it be best to weld the tabs together, and leave it one piece? I'm going to have this coated before it's ever run, would expansion and contraction ruin the coating at the seam? I can install the entire thing in one piece from underneath, by having the car high enough and jacking up the front motor mount. I'll be posting more on this build in this section, it's a little different then most modern builds, as it's carbed and everything is done old school.