How would I modify civ4 so that you build horses and units seperately, but the units could mount the horses if they were on the same tile. (you would "load" the units onto the horses, but it would destroy the horse ad the unit and create a mounted unit.) This process would also need to be reversable.

Yes! I would love to have "Dragoons" and Dismounting "Horse Archers"
Also.... I would also ask if Colonial Muskets STR 11 is good because it is a big jump and RedCats aren't even Riflemen... they use muskets.

Meabee, with some SDK code you could transform a mounter unit to a dismounted unit and back again

If somebody can make this change or even feels he can....... why don't you........ START IT ALREADY!!!

i'm pretty sure sureshot did something like this for her modmod to Fall From Heaven. here's a link (http://forums.civfanatics.com/showthread.php?t=193094)to her thread, you can ask her how she did it.