IRule for reverse proxy with http rewrite

When i type in my test URL, it is switching to the external address in the address bar.

I type: 

http://www.opco.com/jobs/apply

The address bar switches to

http://www.newsite.com/mobileapply/opco

Here is the latest update:

The company wants the user to type:

http://www.opco.com/jobs/apply?postingid=1235213&vendorid=2214&return=https://m.xxxxx.com/Job-Search-Results.aspx?countryName=All&state=0&domain=&keyword=java

it should forward to:

http://www.newsite.com/mobileapply/opco? postingid=1235213&vendorid=2214&return=https://m.xxxxx.com/Job-Search-Results.aspx?countryName=All&state=0&domain=&keyword=java

The user never sees the new site address in the address bar.

This is the current irule that I have.

when CLIENT_ACCEPTED {
    set default_pool [LB::server pool]
}
when HTTP_REQUEST {
    switch [string tolower [HTTP::uri]] {
        "/jobs/apply" {
            HTTP::uri "/mobileapply/opco"
            pool newsite.com
        }
        "/jobs/apply/resume-thanks" {
            HTTP::uri "/mobileapply/opco/thankyou"
            pool newsite.com
        }
        "/jobs/privacy" {
            HTTP::uri "/mobileapply/opco/privacy"
            pool newsite.com
        }
        "/jobs/terms" {
            HTTP::uri "/mobileapply/opco/terms"
            pool newsite.com
        }
        default {
            pool $default_pool
        }
    }
}

Also, if the user just types in http://www.opco.com it should go to our default pool called opco_pool. When i tried to add that to the rule, it kept failing. Should i put the default pool name in this line:

set default_pool [LB::opco_pool]