its time for me to start building my 360..

ok after months of deciding, being lazy and not wanting to work on it due to being cold, its time for me to start to finish my project. i bought a shortblock a few months back and just now getting to it. right now i just want a basic engine, nothing really fancy, i dont even think i need to bore it right now, just hone. i just have 3 major questions right now.

i have a 73 360 block, casting # 3418640-2 with an x. now what does the X on the crank mean? under or oversize?

also it has the heads 4027596, and its had port work done, are these good heads?

i dont think i will have alot of hood clearance, so what is a good single plane intake thats low but still delivers good power?

the rest of the motor is still up in the air, it depends on what kind of deals i can get, and what kind of room i have under the hood after i mount my motor (waiting on rear sump oilpump to do that)

ill post photos after i get my mounts done.