Sounds like you are well on your way!
I am sure if you do a search on heater removal you might find what you are looking for... sorry to say I do not have that answer!
I am posting the link to my hubby's thread that shows the process we went through to restore our 1963
Bambi. You might find answers in the future to questions that come up... he has lots of pictures, etc. to help explain. It is a long thread, so grab a cup of coffee and check it out!
Good luck and post pictures soon! Caravels are great!
Mrs. NorCal Bambi (traveling in S Tardis)