That's insane. I've never pulled or installed a diesel in these trucks but I've done countless small blocks and a few 460s. It's a 1-2 day job, worst case with turbo swap surprises and a lack of motivation you'd be looking at 20 hours, and $100/hr is nuts even with the overhead of a shop. If it was local I'd be happy to rescue your truck and bill you actual hours at $50/hr with a guaranteed max of 20 paid... Significantly less if you came and helped over a weekend. I mean, if I am understanding this correct in that more or less you got a new engine ready to go and a dead one bolted in.
I had an engine failure with a 460 from inadequate octane and had the engine out, freshened up, and back in, over a weekend. Totally tore down to bare components and rebuilt with new rings, bearings, cam, gaskets, everything cleaned, measured, and documented. If it needed machine work I woulda been delayed, but it didn't. I'd say that job I might have been in around 40 hours from Fri PM to Mon AM doing it solo except I had a buddy stop by for about an hour when dropping it in to help get the trans lined up. No way a simple out and in is gonna take 40 hours even with typical BS problems to run and get a part or bolt.