you are in luck
hey jed the 347 motor is based upon the 302 block you already got in your truck. there are 2 was to go about this. a 347 kit cost bout $1800 or full built 347 motor fo about $2800. i would reccommend that you get the full motor beig that i doubt you have a forged or billet 302 block just sitting around in your garage, that way you know the block will handle te even bigger horsepower you will make later. i would go 347 before turbo anyday. just because it would be a little cheaper depenidng on what hookups you got, alot less time consuming, and made for your truck. you also have the 5.0 liter so it already has a great tranny in it, the 4r70w tranny is a really strong tranny, put a shift kit in it and like i said set it firm and you wont have any problems busting through 400 hp with it, unless you got an unusully high amount of miles on it. to me i consider the 347 like a BIG bolt on. there is not alot of fabrication that goes into one getting installed. unless you want the mustang options and accessories you need the mustang front drive assemblies, which we wont get into quite yet. if you want to break 400 at the rear just go with my list above all the way through my stage 1 and you should be at about 400 rwhp right there. unless anyone else can reccommend anything better or cheaper. yeah you could get the 347 but with that and the heads and cam and headers, TB, intake you are talking about another 6 grand in that alone too. let me go through a parts list and see how much it would cost(average jo cost). 347 motor $2700, s/c bd-11 kit with6 psi pulley for $2950 or for an xb-1a kit with 9 psi pulley costs bout $3800, victor 5.0 intake cost bot $550, exhaust costs bout $400-600 depending, superchips "flipchip" costs bout $400, NO2 dry kit costs $750-950, canfield heads stage 1+ ported costs about $2000, Pro m mass air meter costs about $300-400, baumann shift kit costs about $170, 36 lb/hr injectors costs about i think like $300ish or so, cam about $300 or so depending if it is custom grind, msd ignition about $400-450, TB go for around $290 w/ spacer, headers about like $350-400 ish too i believe. and i think that is it. anything else i missed guys? as you can see to do it right takes alot of money but it is sure going to be alot of fun to get there. lol. well hope this gives you a better understanding of what line you would want to pick to go through. let me add this all up for ya real quick without labor costs thoug alot of this stuff for labor could be done by you or by a buddy that knows what they are doing. ok soabout $13000 for all parts needed tomake well over 575 rwhp. labor depends on who you know. by the way that is with everything on the list at the high end of the estimated costs, including xb-1a s/c instead of a bd-11(if you are gonna go that far then by all means dont weigh yourself down with a bd-11 that can not run as much psi as you would want to run safely. well there ya go and if anyone has anything to add to what i said or quoted that is cool, sometimes i leave some thing out that i forget to mention. good luck.