No. You would need to bore the block to 4 inches, which is too much for a 305.
Yes, and well.
Yes, it will fit.
Chevy didn't make a 306. A 302, 305, and 307, all of which will work just fine.
That would be a destroked motor, and would result in a 285.
305 327 350 400 283 with a little modifications
the biggest difference is obviously the stroke and bore of the engine and the size of the engine
Yes, a 283, 305, 307, 327 etc will fit. You should be able to use small block motor mounts from 1966
Higher compression ration which can increase hp. I installed 49cc heads on my 305 instead of the 64cc and got a higher compression ration and a fair amount of hp gain.
The 305 shares stroke dimensions with the 350, so if you put a 327 crank in a 305, you'd have a de-stroked 305 with almost no compression. Displacement would be around 287 cid.
Yes, they should bolt on just fine. Might get a little more low-speed torque with a decrease in top-end horsepower.
Probabaly either 285, or 300. The high performance 327 was dead in 68, as they had turned their attention to the 350 by then.
yes the heads will bolt right on but if you are putting a 305 in there the flywheel is different in the sense that the 327 has a small hole where the flywheel meets the crank (you need the starter for the 305)