I have a 280 sport with twin 454 mags. Manifolds and risers need to be replaced. It is all stock and I have no plans of changing that. My current set up is cast and the spacers are about 2" tall but look like they where cut or ground down at some point (hell, as short as they are I am not sure the boat even needs spacers). I am Tring to learn what manifolds and spacers (if any) folks are running on similar configurations to help me pick a system. Thanks.

You shouldnt need any spacers on that set-up...unless your transom was re-done and X-dim is higher now? But I doubt that.

I would go with a set of Gils or EMI for reliability and low cost.

No - the transom was not redone and it has the stock swim platform on it with stock thru hull exhaust that comes out under the swim platform. I spoke to a couple of folks that sell the EMI manifolds and they said I needed to go with the stainless risers and not the cheaper aluminum risers (adds about $1,100 to the price). I assumed that the concern was riser height and not reversion as I told them I had no plans of changing the stock cam size. It would be great is I could use the cheaper aluminum risers. Thanks for the input!