Mike......... you cant show us that and not say what the engine is!! I ended up going a similar way with RHS manifolds on the Iveco 2.5 tdi and it is far more pleasant not having the exhaust manifold roasting the side of your leg!
I have a further mod to make after last weekend though............ doing some extreme brush cutting in the unseasonable heat with a trailed mower on steep banks....... I boiled the power steering fluid!! So a cooler is now being devised!