how should i go about building....

Hello, i am new to this list but if it is like the others i belong to i am sure it will be wonderful wealth of infomation. A little back ground info. on me and my unicycling is i am a 17 year old kid who loves a variety of interesting hobbies. Unicycling is a definiate favorite and i have 4 unicycles that have accumulated. first one from the neighbors trash bought the next two and then made a mini-giraffe out of my first bike and a scooter wheel. nice but highly impracticial. I have just bought my 5 unicycle tonight from a friend in hopes to build a unicycle like the second one down on this link … http://www.unicycling.com/garage/multi.htm
Has anyone ever concured the task of building one of the sorts. I figure with this unicycle i can have a base to start my project. Any ideas what to do…or how to go about it? i have a few but just want to see what other people opionions are … thank you for your input