Welcome to the Forums,
Just giving you a heads up though... Most people on here don't spoon feed you info.. you'll probably get flamed too if you post something like this in general chat as well.
Google and the "Search" function on this forum are your friends. You can find the solution to almost any issue through those.
If you google "S13 5 speed swap" you'll get this:
How To: 5 Speed Swap in Convertibles (and other S13s) : 240SX Convertible Forum
I haven't done it yet personally.. but it seems like most people get the tranny and anything else they can find from the junkyard to save on $$. The general consensus for cost to go from auto --> manual seems to be ~$500