These are some of the 1/72 figures I used on my HMS Victory diorama.I was lucky in this case, to find figures of the Napoleonic era, that required mostly the removal of plastic to convert them into what I wanted.
Some I just changed the uniform from infantry to marines,while others I radically changed from officiers into able seaman.I used three different sets of figures to crew my ship.When shopping around for figures try to see beyond the obvious and look more for body and hand and feet positions that could be used "as is" or could be slightly modified for your purposes.
I understand that the plastic used by different manufactures can vary quite a lot in consistancy.I found that with these Revell figures that you could cut them very cleanly with a #11 blade but they are hard to work with any kind of rotary tools.I don't know if the same is true for all plastic figures,here you will have to experiment a little as my knowledge in the area is limited to only one brand.I have had more experience with resin figures and rotary tools, which are very easy to work on with burrs.
These plastic figures are quite nice and have a lot of detail for such a small scale.They require very little clean up and flash can easily be removed by cutting it off or scrapping with the edge of the xacto blade.
The mods that I show here are about as radical as I have done to a standard figure without actually moving, replacing ,or mix and matching body parts.Here I was looking for hand and body positions that could be modifed into figures that were hauling on ropes.These guys are obviously "factory rejects" for one reason of another but they give you an idea of the process.
I also used some "mounted on horse "figures from the American civil war era for some of the seated figures.Other seated figures were from wagons and they would make great sailors hauling on oars or a seated figure for aircraft cockpits.More on this later......