I currently have a 89 7.4, 330 hp. I'm thinking of pulling that motor and replacing it with a new 496HO or HP500, but I have no idea about cost. Am I better off building my motor, or doing the switch. I know there are motors out there that are avaiable (Teague, Rex, etc) that I can buy, but I'm just not sure which way to go. HEELLPP??