Your best bet is to find a junked Altima in a junkyard, then get all the parts you need. One of the Topnotch guys did it, his name has Topnotch in it...can't remember. The list isn't too short, but it can be done.
It was Topnotch Til I Die (altimatt san diego). He basically did it b/c his tranny was dead anyway and he could get a nice deal on the parts & labor. So it isn't a good choice for everyone. You should just take everything off you car and buy a new one if you want a 5-Speed.
I think if you have the tourqe converter along with a modified vaulve body then you will achually be faster than a 5 speed but thats also a little more than 1k with install and iv heard with the vaulve body they give you stronger pumps, so if the place that installs it dosnt run bigger hoses that they can break and your tranny will be dead.