Need HELP! Need to move site to new domain without herting..

[roro]

Hello, The SEO company I work for just sold a well ranked website for a spa company in Utah because the Spa company went out of business and does not want their web site anymore so they handed over their well ranked web site to us so we sold it for a hefty price. Now we need to convert the look of the web site and the company name through out the entire web site ( keeping the same domain ) with out loosing any page rank or positioning in any search engine. What do you guys think is the best way to go about doing this? http://www.canyoncovespa.com/ I just spoke to my co worker and we would like to be able to drive all of the traffic for http://www.canyoncovespa.com/ to http://www.xscapedayspa.com/index.html. What do you guys think is the best way to go about doing this? Thanx, Jacob WI Works, Inc. - Web Development Engineer