I just got the old manifold out -- it just pulled out through the top of the engine compartment. All the bolts wrenched off with little issue, which was a surprise. I think what helped though is the clamp at the rear of the cat was loose, so I loosened it further so the cat would drop enough to clear the manifold studs (with some prying). For assembly I'll wait until the manifold is in place before putting the new studs in the cat flange. I havn't had to touch the rack yet except to tie it off to the body when lowering the subframe for the clutch job. I suspect you will need to lower the rear of the subframe to access it.