Discovered a small (1 1/4") crack in my exhaust down pipe. My question is, at the "seam" pointed at with red arrow in the pic, is that a welded pipe inside pipe (like a slip joint) or is it a same diameter pipe to pipe weld? Additionally, though this is for info only, why the small run of dual pipes exiting the exhaust manifold? Only thing I can think of is for back pressure for the computer (which I no longer have). Believe the carbed 86 and older models were a single pipe exiting the manifold. Additionally, I plan on removing the manifold and pipe by removing the 2 bolts at the flange where the pipe joins the flex pipe. Is that gasket just a standard size exhaust gasket which the shop should have or will it be something I must order from Jerry, online, etc?