Elliot ,
In any restoration you can never have enough diagrams of what goes where ! Different angles , different perspectives … they all help you to figure it out.
Can I recommend , if you've not got one anyway, a free Morris Minor catalogue from Moss
www.moss-europe.co.uk . I see that they are on Issue 11 at the moment. My copy , Issue 10 has a
good "end on " sill structure diagram on page 74. It probably hasn't changed on the latest issue but if it has it will be on a page , back or front from there.
A number of the main Morris Minor suppliers also have good diagrams on their websites to reference.
What ever you do , a couple of
Golden rules. Only do one side at a time ( so you always have a point of reference ).
Secondly before going mad with the angle grinder / unpicking spot welds , etc. do take loads ( and I mean loads ) of measurements from fixed datum points , that won't have moved when you take things to bits.
The strength of the car relies on the panels being joined together correctly , in relation to one another. A monocoque construction.
Brace the door openings ( assuming you're happy with the gaps around the perimeter of the door ) with a
strong metal bar, say 1" / 25 mm thick , by 1/4" / 6 or 7 mm thick , by the length of the gap , ish !! It has to be sturdy. With door seal rubber removed clean up a small section of metal flange to enable you to weld the bar in.
DON'T weld it too close to the area you want to weld new repair panels to !! Allow enough "wriggle" room for your welding torch to get in there. You may also want to brace across to the central transmission tunnel , if things are so bad that you're having to replace complete floor pans , rather than just little sections. You can remove the bracing bars , ready for the other side of the car , once all the new panels are in situ. You'll do the
other side in half the time … now you know what you're doing.
If you've not removed " everything " remember that molten metal from either the grinder of the welder will quickly ruin - big time - paintwork /carpets / interior trim / rubber / steering wheels / instruments / interior roof lining /seats and not least glass. So if you can't remove , protect with sturdy , very thick cardboard or plywood ,etc.
Study as many diagrams as you can , make replica joining assemblies out of cardboard if it helps you think it through. On another Classic car I had a complicated B post joint where 7 pieces of metal came together.I made a little cardboard model and spent 3 days trying to figure out what I needed to weld to what and in what order. Remember you can't weld to rusty metal and you can't weld to "thin air " when you've already cut out a bit !! You can only start from a solid base of clean metal. Remove
j u s t enough metal to get the first repair section and build from there. Same process. Try to avoid hacking out loads of panels , making big holes all in one hit. You will only make things more difficult for yourself. Check those measures you took against your work as you go. On to the next bit , check the measurements again and so on.
There are lots of restoration threads on the website , as have been mentioned. So worth reading.If you still get stuck don't be afraid to post again. A photo speaks better than a page of words every time.
Good luck with it Bob