you can obviously do it, its not that complicated, you just need to know where to make things strong. and I do believe it will cost a little more then $200.
first, your frame tie in. you definately have to beef up and support the frame with additional metal if you plan on bolting into it. I made a new crossmember out of rect tubing 3/16" thick, and welded some 1/4 plates to the frame and drilled and tapped 1/2"-12 bolts. totaling 6 bolts on each side. and welded the tabs for the long arms high up on the cross member so it barely hangs down.
as for the control arms, you shouldn't just add a foot of metal inbetween. just cut off the two eyes off, and weld in a new tube. i used 2" OD 1/4" DOM and weld on the upper control arm mounts to that.
of course without pictures it doesnt' mean tooo much, I'll try and snap a couple tomorrow and post them up so you get a better idea. Look at Rubicon Expresses website or few others as well, you can get some ideas on how they design the setup. but dont be discouraged into not building it. just plan it out, and build it carefully.