Can definitely relate to that scenario.
Strange how quick logic goes out of the window in a brief moment of panic.
I once changed the engine on my nephews Turbo charged XR2
He didn't tell me that he had fitted one of those fangled gadgets on that keeps the engine running for a while after the ignition has been turned off ( Supposedly to allow the turbo to spool down properly ??
)
After first start, I immediately noticed a major oil leak, quickly turned the ignition off.
Imagine my shock when nothing happened, blind panic when faced with the reality of a newly rebuilt engine likely to go pop ( I jumped in & stalled it on the clutch )
Turned out that I had not fully tightened the turbo's oil feed pipe
( Thankfully, no harm done )
All that aside, it is not uncommon for a manifold to glow a bit when very hot ( very noticeable in poor light conditions )