Just a few things i don't fully understand. When i decompiled the vulture there was 000-016, i replaced all the images with what i wanted, but say i wanted to replace it with something with more or less frames, can i just delete the unneeded ones? Or with something with more frames, can i just add them in? Is there any way to do that? Or would i just have to use a unit with the right amount of frames i need?

I'm pretty sure you have to stick with the original amount of frames that each unit has. Maybe you can edit its iscript to allow for more/less frames, but I think that only works for walking/attacking animations, not for portraits.

Nah, deleted frames will cause programs like RetroGRP to crash when compiling the new GRP. At least for me. What I do is like, if I want to give the vulture attack frames, I alter the Scout since it has the extra frames then, compile it into a new grp then just rename it to vulture.grp and problem solved. There might be a more simpler method out there that I'm unaware of since a lot of the methods I use for modding are incredibly old.

PyGRP from PyMS is an excellent, bug-free (AFAIK) program compared to RetroGRP and fulfills the same purpose with much better features.

*.grp files can have as many or as few frames as you would like. The only restriction is imposed by any scripts that use a specific *.grp file -- scripts can only refer to frames that exist in the *.grp file, else SCBW will crash.

Thanks everyone completely answered my question and then some haha.