I have the 79256 coated headers for my 78 440 Power Wagon. I believe these are the same as the 79250 headers, just coated. Most of these I have seen are fitted to iron heads with straight plugs. I am looking to upgrade my 906 heads to aluminum, and many are with angled spark plugs. Selection is pretty limited if straight plugs are required. Anyone know if these headers work with angled spark plugs? Any specific aluminum heads that have been used with these truck headers? Any information would be greatly appreciated.