You must be mistaken.. Ford Flathead is a boat anchor and totally not right for that car. That my friend, would be ridiculous.
What did you use for a motor harness and ecm? I ended up with an extra '06 6.0 that I need to find a use for. Did you delete the m*** air?
What are you doing for engine management? I see you have no MAF, but weren't the stock computers speed density and MAF with a default to either? Anyway, I am a Ford guy, but that LS looks right at home.