Unless FAQ's are configured to be only visible to Techs, clients should see FAQ button/link in the header along with Request, History, Profile, etc.
If you want it to be more obvious, you can set the FAQ view to the default view at client login via Setup > Clients > Options > Default Client View: FAQs
The simple answer is no, not unless you want all FAQ's to be displayed when you select the first Request Type that you've mentioned they only have access to.
What Justin has said would be appropriate in most scenarios, however if you have limited the Request Types the client can see, then these FAQ's that have been categorised will also not be visible here.
Thank you for letting me know.