I created a Custom list New Form and need to make the text fields read only

When I use SharePoint Designer and add the read only attribute  to the  SharePoint form field, then it throws  a web part error.

but here is the thing, I have current user Filters populating the Form Fields. So the form fields  populate First name , last name etc. and I need these fields read-only....

the Client doesn t want the end user to Change those fields.  Is there any way to "LOCK" the form fields?

As I have only 7 text fields that need to be locked down. and one field is a signature line that is a true input field.. where the  user has to inter their initials.

Any ideas? as I have tried most of the items available thru searches nothing works, or it throws that web part error message.

Steve Athey