I would like to see an uninterrupted video of a 35 minute swappy swappy. Even in my young days I couldn't pull out a running engine then get another engine in and running in 35 minutes.
I did it on an SB with no a/c, no PS and manual brakes and manual trans. and it had headers.
I started with draining the radiator so that it could be draining as I did other things, disconnected the headers at the heads, lose the motor mount nuts, get rid of the z-bar ( to protect the little white bushings) lower clutch covers bell housing bolts, pulled the clutch fork back (not out just back) ....throttle cable.
Last was get rid of the radiator, connect the engine and yank.
OK, my mistake ....it took 30-35 to get it out ......took another half to 45 mins to get the other one in ......sorry brain lapse......I see what you mean now, to get the old one out and new one in all in 35 mins would take wonderwoman or superman........but still the point is that on a lazy sunday afternoon it could all happen very quick.