Woah, the 427 is a cousin to the FE engines like the 390, 352 or 428. You can stick a 428 crank in a 427 and end up with 454 cubes.
The 429 and 460 are alone one family, called the 385 series.
The 385 series has the largest bore spacing, and thus largest piston capacity. Any 429 or 460 can be bored .080 over without checking, or as much as .160" over if the walls are perfect.
The 351W is an excellent engine to build on, all the way to a 427 as Xan listed. Those are run in pro off roading classes, making 650HP+ with fuel injection.
The Cleveland was the best small block ever built by any American company, the smaller crank journals are the biggest advantage over Windsors, which is why they are used in NASCAR. The combination of Cleveland and Windsor parts can get you the best of heads, blocks etc, but most is high end aftermarket stuff.
Stick with the 460 and stroker kit things Burns, there are tons of parts and most are reasonable. I avoid "crate" engines because by definition they include a few expensive parts that you typically don't need or would choose. You want the best cam for your application, as well as a different compression, carb or distributor, heads, rockers etc. If you get a crate engine you need to build a vehicle for that rpm band/usage. It is rare for that to match what you want. Regards,