What would be the cheapest way to replace the stock 250 i6 motor from a 1975 ford maverick 4dr with a 500-600 hp motor and what all modifications would need to be made. I have already thought out the suspension and exhaust all i need is the motor info. Would a dss racing 331 be better then a newgen supercharged cobra motor. Will either of them fit reasonably well as far as the walls go, the hood is not an issue it can be modified. What transmission would be good for this application?