73 400ci Head change out Questions!

[Als73charger]

   I am in the process of installing re-built 516 heads on my 400.
  I will be replacing the OEM 2 barrel carb/intake with a Carter AFB 4 barrel(650 CFM)/Eddy Torker intake combo.
  I noticed when pulling the intake off, fiberglass insulation was placed between intake and valley pan. Should I re-install with the new intake/pan? Will this be required?
    Also, I do have a 1" aluminum spacer for between the carb and intake.  Any benfit in installing this? If so,will I have clearance with my stock hood?
   I am wondering about whether or not to leave the exhaust mainfolds on the heads for removal and unbolt at flanges or remove manifolds from heads instead(engine still in car). Any pointers?  Al

[RallyeMike]

I noticed when pulling the intake off, fiberglass insulation was placed between intake and valley pan. Should I re-install with the new intake/pan? Will this be required?

No need for it.

Also, I do have a 1" aluminum spacer for between the carb and intake.  Any benfit in installing this? If so,will I have clearance with my stock hood?

You don't need the spacer. Fit with or without it will depend on your air cleaner and what type of base it has on it (dropped or not, how much it is dropped).

I am wondering about whether or not to leave the exhaust mainfolds on the heads for removal and unbolt at flanges or remove manifolds from heads instead(engine still in car). Any pointers?

Take the manifolds off first. The heads will likely have to be pried and you don't want to fight it too much. Also, your back will be happier. Soak the bolts of the manifolds with penetrating oil for a few days first. Have a shop vac and rags handy to clean the cylinders of spilled coolant after you pop the heads.

Have fun.

[Als73charger]

 Thanx RalleyeMike!
  I am using a stock air cleaner.
I will go and spray the manifold bolts again, before I attempt to take the manifolds off this weekend.  Al