[MrPbody]

Mr. Horsepower, at the risk of opening an arguement, I must disagree. First, that all the 350s are the same. The pre-79 blocks are a bit "harder", containing a higher amount of nickel alloy. Some of the "performance" blocks are said to have even more.
The distick tube installs on the driver's side (left) up to '76. After that, it was on the other side (exceptions here and there, but in general...). There are factory "warranty" blocks with the tube provision on BOTH sides.
Also, for a stroker, a 4-bolt is highly recommended. Considering the majority of early (pre-77) blocks are 4-bolts, it would be prudent to get one. We have seen main bearing issues with nos. 2 and 4, when 2-bolt blocks were used, and the engine was used in a performance application.
We have also seen significant problems with the cast steel cranks out there, on nos. 2 and 4. We suggest either the factory 400 nodular crank be turned down to fit, or go with a high quality forged steel crank. These have shown to live in an engine designed to make power.