MT, if you're going to carry a grill, which, from my perspective is the best way to cook a meaty fish like trout, then there is only one for you.  I can't believe you don't already own a Purcell Trench grill.  The best one for your purposes would probably be the Streamside Voyageur Grill.  They are pricey but absolutely the best, lightest and most durable grills available.  I have a couple that I've been using for 10 years.  These grills are absolutely brilliant.  One of the best pieces of gear you'll ever own.  Honestly.  I don't get a penny for this endorsement.
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