Dauntless 225 odd fire question

Looking for some assistance regarding the V6 Odd fire identification. When looking for parts, ie. HEI distributors, manifolds etc. how does on know what will fit and what won't. Do all buick V6 parts interchange? Are the engines the same regardless of transmission type. Can I use a engine that came out of a jeep w/ an automatic and put it in a jeep with a standard? or visa versa. I'm asking because I read somewhere that engines that were used with the automatic were internally balanced and standard transmission engines are externally balanced.
While were on the subject I understand that there is two flywheels available, 75 lb. and 100 lb. I'm thinking more weight would equal smoother running and more torque. I'm sure you'd sacrifice a little bit on responsiveness though.

Any thoughts?

 

A lot to answer but heres a couple.
The odd fire has a different dist than the even fire. Internally
the odd fire flywheel that comes in jeeps 225 is about 50 lbs, just had it out.
no other oddfire has this that I know of.
Oddfires are external balanced and evens enternal balanced.
All buick v6 (225 231) intended for rear wheel drive should be same bolt pattern. For the tranny mount auto or manule.
google is your friend on this subject.

 

the hei dist will fit from either the odd fire or even fire 231 buick. There is tech article on converting an even fire HEI dist to an odd fire. Works well.

The Exhaust mainfolds fit fine but look flat and triangular even use the same gasket. I used the driver's side from 231 monza for the driver's side in my CJ when I converted to power steering.

 

One thing you might come across is a 231 (even fire) without the crank drilled for a pilot bushing.