Is the Svea 123 or 123R rated for auto/motorcycle fuel?  Mine (I have three) specifically say white gas only.  I do have a small clone of the Optimus 8 that calls for white gas (coleman fuel) or regular unleaded.  The problem with auto fuel is it still has lots of additives you don't want to be breathing.  
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Better is the Enemy of Good Enough.  
Okay, what’s your point??