Greetings all,

I just purchased this: http://imgur.com/gAupk

I'd like to convert it into a fixed-gear, or at least a single-speed.

Issues:

1) The guy who sold it to me said that the headset is threadless.
However, upon examining pictures of other Samurais, it looks like quill stems are being used:
http://velospace.org/node/15454
http://bikejournal.com/images/paulbonnersamurai_1.JPG
http://ridewithgps.com/photos/full/12091.jpg
http://3.bp.blogspot.com/-mV6-mG-5Oa...0/DSC_3075.JPG

My headset (pictured below) is a Levin CD Tange, which looks like it came with the bike, and doesn't look dissimilar to the bikes pictured above:
http://imgur.com/2ODMR

Does this mean that he was wrong and that my headset takes quill stems? If so, how can I tell which size I need (or are there even different sizes)?

2) I am poor and unskilled. Is it more economical/efficient to build my own wheels, sprockets, and cartridges from parts I find on eBay, craigslist, and Amazon, or should I get a Thruster from WalMart, harvest its parts, and sell the frame?

3) Is it possible to use hybrid wheels on this, or would I be asking for trouble? The fork is like 40-45 mm wide at its narrowest point. Pedaling through grass and hopping curbs is more important than speed to me.

4) Are these dropouts safe for a fixie, or should I opt for a single-speed?
http://imgur.com/4drTP

5) Is this an exhaustive list of what I need? Do I really need specialty tools (bracket wrench, caliper, etc.)? I have ALL the allen wrenches.

a) Wheels/sprocket/cartridge/skewers
b) Bottom bracket & spacers/crank/pedals
c) Stem/handlebars
d) Seat
e) Chain

6) Thanks!