the stock 69 351w heads will make great power with a basic home porting job. the main thing to concentrate on is the exhaust ports which have the goofy thermactor bumps, those need to go bye-bye. open the intakes just a little bit, really not much more than a good gasket match but blended a little further in, and smooth everything out really good with extra attention paid to the bowls. you could even use the stock sized valves but make sure to use stainless vlaves with undercut stems, the difference between 1.94/1.60 valves and the stock sized 1.84/1.54 windsor valves just isn't really enough of a gain to worry about IMO, you'll get more flow from the undercut stems and the valves won't be nearly as shrouded. there is a reason why ford STILL uses that size on most of the FRPP aluminum heads.
you can also keep the stock valvetrain and still get screw in studs if you prefer the stealthiness of that type of system. Mr gasket and others make a conversion kit to convert your stock heads to screw in studs without having to use guideplates, basically you just have to tap the stock rocker stud holes and screw in the new studs.
i would also CC and polish the chambers and try to open them up just a bit to around 64cc, this will give you right around 10:1-10.25:1 static compression with stock style flat tops which should be just about right provided you have the right cam to bleed off some of that static compression.
you could go with a set of power heads CNC ported stock heads,
Welcome To POWERHEADS. Your High Performance Engine Specialist for a really radical set of ported stock castings but they cost almost as much as a decent set of aluminum heads and easily as much if not more than the cheapo aluminum heads.
FRPP has a nice of aluminum gt-40 heads with stock size valves and late modelbolt down rockers that will work perfect with some 93 cobra/crane energizer 1.7 roller rockers and you have a choice of 60cc or 64cc chambers. yes there are better heads out there but throw a coat of ford bluse engine paint on these and nobody will be able to tell them apart from your stock iron castings without tearing the valve covers off or using a magnet, they even have the stock style ford freeze plugs in the ends of the heads unlike most aftermarket SBF heads, which is one of the main reason i like them, plus the bolt down rockers so i'll be able to use the inexpensive cobra roller rockers, which are also available from FRPP as well.
i like sleepy, stock looking engines in my cars so i'd opt for some seriously ported stock castings or the FRPP's for my car, but that's just my choice and everyone has their own choices.
