If you have tools and access to a lift, it is not bad at all. tools and a buddy are probably the best things you can have really. that will save you labor costs, which would run you about 4-5 hundred dollars from a good place. as to the parts you are going to need based on a new edge:
1. transmission obviously 500
2.manual ecu (you can have your auto shift points removed on your ecu if you want, but i have never had experience with that) 85
3. transmission wiring harness (check salvage yard, prestigemustang.com will hook you up with anything you need for this job at a good price) 30
4.clutch kit (pressure plate, clutch disc etc) 160
5. pilot and throwout bearing 50
6. clutch cable, bracket/s (you can fab em yourself) 45
7.pedal assembly from manual car 125
8.flywheel and probably new bolts (should be 6) varies alot 80-700
9. clutch pivot 20
10. little dust boot on side of tranny (little rubber box thing, 60 bucks from ford)
11. clutch lever/release 35
12.shifter and knob 200 for mgw or good one
13. drive shaft (you can use your old one if you can swap the yokes etc. honestly i would just get an aluminum when i was under there) about 200
as to it being worth it, i say go for it because you can install improved parts all in one swoop and have a beefy drivetrain. unless of course you can get an awesome deal for you car and on a new one. also take into account what you have done to the car already.
mind you all these prices can really vary from source to source.
i think that just about covers it; there may be some odds and ends i forgot. should be about it though. check out ebay, prestige, summit, jegs, and your dealer etc and you can save some bucks.