I thought the shield was ugly, and decided to take it down, forcing me to find another way to address the problem.
When I did, I got a pleasant surprise. Behind the heat shield was a metal grill with adjustable vanes, venting from the plenum just behind the heater. This was a left over from the original air conditioning installation, at that time mostly removed. For real air circulation, I got a 12V electric radiator fan from an automotive shop, and mounted it in the plenum behind the grill. These are designed to move a lot of air, and are pretty bullet proof, being intended to run outside, under the hoods of cars in all weather.
Next, I thought the metal-framed grill was also kind of ugly, so I made a teak bezel for it. You can see how I have set the vanes to blow the heat away from the bulkhead and ceiling, and out into the boat proper.
Next on the agenda was the treatment where the chimney pipe penetrated the deck. Outside, it was fine. But inside, the trim installation left something to be desired.
A hole had been cut in the headliner, and the trim ring supplied with the Dickenson had been installed to the deck with long screws (the headliner is about 1" below the actual underside of the deck). But the headliner hole was ragged and oversize, and the trim ring was not large enough to cover it.
I glued some wood scraps to the underside of the deck with Gorilla glue (great for large gap filling), scraps thick enough to fill the gap between the deck and the headliner. And I made another teak frame large enough to cover the headliner hole and have some reveal around the stainless trim ring, and attached it to the now-glued wood scraps, trapping the headliner between.
Oh yeah, and I took down the little 12V fan and its associated wiring.
This arrangement works very well for heating the boat, and I think it looks good too. Don't you?