Ford states that the SVO is worth a solid 30 hp, just incase the question was in the air. SVO heads un ported are worth anothe 30 hp. Port them and gain around 40 hp. Wicked streetable cam around 25 hp. Big bore block 40-50 hp.
175 hp gain, not including bolt on's. Add that to the 215 hp factory number, 390 hp. Add full exhaust, 25 hp (full potential because of motor.) Intake parts, CAL, T-Body, MAF, 25-30 hp. Tune. Easy 450 hp. and with 16 loss to the wheels you'll be packin 373.8 rwhp. And still have more hp to grab if you get ride of power steering, a/c, electric water pump. Which would carry you to around 400 rwhp. Then I'd buy an aluminum drive shaft. Actually, I'm explaining what I want to do soon as I get my job in accounting.
Then slap a 150 shot for 550 rwhp.