Web Accelerator and X-Forwarded-For

I have a new WA deployment. I am using a redundant pair of 6400 with the WA feature. I am running 9.4.5 HF2.

This is my typical LTM configuration that I am using for a give site

monitor site.com_monitor { 
 defaults from http 
 send "GET /bigip/bigip.html HTTP/1.1\nHost: site.com\nConnection: Close\n\n" 
 } 
  
 pool site.com_pool { 
 lb method predictive 
 action on svcdown reselect 
 monitor all site.com_monitor 
 members 
 10.1.1.1:http 
 10.1.1.2:http 
 } 
  
 profile httpclass site.com_httpclass { 
    defaults from httpclass 
    wa enable 
 } 
  
  
 virtual site.com { 
 pool site.com_pool 
 destination 10.2.1.1:http 
 ip protocol tcp 
 httpclass site.com_httpclass 
 profiles 
       oneconnect 
       tcp-lan-optimized 
          clientside 
       tcp-wan-optimized 
          serverside 
       http-acceleration 
 } 
 

and I use a modified version of the Level 2 policy for the site. What I am wanting to be sure is that my web access logs on my web servers have the correct client IP address for request, so I would like to insert the X-Forwarded-For header using the HTTP profile. I would prefer not to modify the http-acceleration profile but to create a new one that inherits from it. When I tried that, I noticed that my hits for Hot Cache went to 0. What would be the recommended way to get X-Forwarded-For header sent to the origin servers - modify http-acceleration profile, iRule, or something else?

Thanks,

Mark