I just got a 1976 Roughneck bass boat. It has a 115 Johnson outboard on it. I just pulled the plugs and on one side it had UL77V plugs and on the other side it had L78V plugs. I really don't want to run 2 different kind of plugs on the same engine and I think they could probably use replacement anyway. What are the best (and cheapest) plugs to put in my engine? Also, surface gap or standard? What gap size if standard plug is used?