One important profile change is the presence or lack of “tabs” above the wheel arches.

All US spec 60 and early 62s will have one on the drivers side as pictured, but only later model ones have this tab, or ear, on the passenger side. It was put in to prepare for the installation of gas door release cables.
Conversely if you have a truck that no longer has the vinyl wheel arch covers or other changes the passenger side panel may be better off being a full (no tab) profile. If the truck has factory rear shoulder belts this area of the profile will again be different, etc.
The lack of a tab on the passenger side can be found on trucks all the way up to 1986.

There are also different seat latch mount profiles- this brown tuck pictured has a fairly rare profile only found on 1982 and some international spec trucks.

On trucks that have had the interior plastic cargo trims removed, or on international spec trucks that did not have the plastic trims I can make the panels to fit the seat latch profile rather than the standard plastic trim profile.
(if you take a look at the slide show above you will notice that the panel pictured does not actually match the stamping around the seat latch, that is because the panels pictured are standard panels that fit the truck with or without the plastic trims, unless speced otherwise I make all panels to match the plastic trims)
In the last picture here you can see a non plastic trim seat latch profiled panel laid over a plastic profile panel. (you can see a bit of the plastic profile panel peeking out)

Including whether you would like any locks.

For lots more info check out the Latch Options Info Page:

Latch Options

This is my preferred setup since these are a utilitarian modification and rear cargo speakers are kinda dumb cause they are going to get blocked/covered with…..cargo.
There is also great storage space above the wheel arch inside the panel when there is no speaker in the way, and this also gives you a nice blank panel to mount things to if you want, like a fire extinguisher or CO2 tank, etc…..
I am by far the minority with this preference though as most panels I build are back-mount setups.

This panel set has no speaker mount and black coated stainless compression latches

The hole is just that- a hole sized to accept a standard 6.5″ auto speaker driver. This requires the use of aftermarket speaker grills that come with the speaker.

Here you can see a panel set with plain mount holes and an outer profile to match a factory rear shoulder belt trim set.

For the back mount speakers There is a ring mounted to the back of the panels, sized for standard 6.5″ speaker drivers. With this system you can attach your particular driver to the panels without modifying the actual panel.
This system works if you are just re-using the OE speakers as well. This is a $75 option and is by far the most common panel I build.

As part of the back mount speaker setup I instal a bulb seal around the speaker mount ring to maintain the integrity of the cargo area seal my panels provide. The quarter panels have air flow through them by design and as such- will (and should) have dust in them as well (keep this in mind when thinking about what you want to store in there)
This bulb seal around the mount ring works in conjunction with the seal around the door opening.
The second photo here shows the seal contact after a hard desert trip.