Happy to help you but I'm in East Yorks. Pm me if you fancy a drive oop north!
Use duct tape to mask off any trim you may be concerned about. While you're at it, get a set of decent trim removal tools that won't scratch. If you know your local body shop well, ask if anyone wants a cash job to swap units for you.
Most us us have done this from cold, and the simple answer is as Leonard says, just take your time. It's very easy to do, and if you are steady, won't take more than an hour.