Hello Again, Looking for Input and Suggestions on Wether I should Install a Scattershield Houlsing or a Stock Bellhousing On my 327 Approx 425-475Hp W/4sp M21 12 Bolt-Posi. Thanks Again...... Looking for Input or Suggestions ...Gary

 

i'd go (and did, on mine) with a stock belhousing but i'm old school

 

I'd go scatter shield with that much power and a posi rear.
I had a big block/4 speed in my '69 but about the same hp as your mouse and I split the stock bell housing in half.
I was lucky the clutch didn't come apart so I didn't get hurt but it was a real wake up call.