Through an 8 inch? Think you need more than an imagination for that - perhaps more like a fantasy!
Suzy, the Horse Head is very doable in an 8" scope
I have definitely seen it on many occasion's in my Celestron 20cm SCT in the past.
the reason I was so flippant was due more to the seeing than the none observation of the object
And It was after all a light hearted report just like the sky was light
Cheers