Making it a 312 vs a .080 over 292 is going to lighten your wallet quite a bit and not buy you an increase in performance worth talking about.
The 272 can be bored to 292 + .080 but have it sonic tested to be sure that core shift is not extreme. Check to see if the machinist has a flat charge per hole as it will take several more passes than usual to do the job and some shops might try and nail you extra.

Instead of looking for 300 ponies, go for a more realistic 275.

As far as heads the easily available ECZ-C should be more than sufficient unless you want to regularly pull 6 grand.
Since you will be zero decking the block plus giving the heads a cleanup cut the compression will be well into the 9's. Consider this to be on the edge for 87 octane and more like 89 if you go the hot cam and ignition advance route for max performance.

With a very similar setup I can easily get the rattles with some 87 octane EPA formulations.

 

No, I just want a real all around driver with lots of power. Eventually I would like to use the truck for long trips and I want a motor that will not be a complete PITA. I am afraid of old tech engines, especially when the price for repairs double the price of a new engine with a modern transmission. In other words I have learned to be more practical then sentimental. I have to admit that the 272 has a real good sound to it though. Especially with no muffler attached. Ed

 

Ok for real. If I want to make it a strong and powerfull engine and I am rebuilding it what should I really do. BTW I am for sure going to go with a AOD transmission. I like the Bluethunder intake but oy what a price? Lets say I want power what should I look for in a rebuild and no special cams or other. Just a complete rebuild back to stock and make it a 292. Ed

 

286 gave you good advice on heads in an above post. Get a '57 up ECZ-B manifold so you can use a modern 4bbl. If you do a stock rebuild the Blue thunder will not be necessary. Use a Holley, Edelbrock, Carter, Autolite, whatever floats your boat. Do some light porting and polishing, which you can do at home. Maybe do a electronic conversion on the distributor and most important take the time to get it tuned right! You can get good, smooth power from a stock engine just by spending time tuning.