What changed between 67-72 and 73-78 models?

[MVHandy]

Maybe a little basic question but I am going to shop for a truck in the next few months. Style and looks wise I like the 69-78 models grill, front end and overall appearance best.
What I am wondering is what the main differences and changes were from the 67/72 generation and the 73/87 generation besides new smog controls starting in 73. It seems that many of the features I would look for or retro-fit (PS/PDB/AC/etc.) are more readily available on the later generation and pricing maybe a little cheaper.
Can the board members share their thoughts help me resolve whether I need to focus on the earlier gen exclusively or am I okay with say 73-78 as well. Does anyone know thedeal on emissions testing if I have a non-original engine? I live in New Jersey so I'm sure whatever the answer is it will not be simple.

Thanks,
Mark

[Longhorn Man]

everything chainged in 73, whole new truck. The wheels may have been the same, but that's about it.
The 67 - 72 were built better in most aspects. However, nonethe less, in your area (mine too) neither generation is all that common anymore, they've all rusted away and returned to mother earth 20 years ago.
Whats your intended use? By shop truck, I assume you meant he fad/trend for a retro look of a retired work truck...and not one for actual working correct?
If that is the case, 72 is the absolutly newest I would ever consider. Its hard to pull off a 60's vibe in a vehicle that diddn't exist in the 60's.

[unclewatts]

I believe the emissions thing varies from state to state. California is the worst.

[b-rad]

Originally Posted by unclewatts

I believe the emissions thing varies from state to state. California is the worst.

i thank AZ is bad too

[Longhorn Man]

you had cali cars, and 49 state cars in smog pieces.
Pollution controls started on trucks in 69.