@TobyB - with a few mods (perhaps similar to yours), we’re at 30 minutes to swap a diff at the track. (worthy of note, no exhaust rear pipe to deal with).
That said, agree with above it’s more than 2 billable hours to swap them both. And as @uai noted, a stuck/stripped brake line / hose adds…. and if someone welded the exhaust sections together, I’ll smack them for you. -KB