Exhaust manifold

[Belsy]

Help!!! Just crawled out from looking at exhaust manifold removal on my 90 to fix cats or install headers and thought there must be some secret to doing this in less than a week? Any suggestions or directions would be greatly appreciated!!
Probably will try headers once I remove everything, any used systems out there? Does motor have to be tilted to gain access to bolts and are there any articles that help ??

Thanks for any help