Re: 4-stroke & jackshaft in a stock 50's straight-bar Panther frame???
Like Scotto said the 200 won't fit without frame mods. I've tried to put half a dozen different size larger motors in Panthers and for clearance here are the largest I could fit HF79 , china 66, whizzer h ( that looks the best and period looking plus they are selling repops on eBay) Briggs 3hp will fits as well.
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