Well guys for those who have read my previous posts I have still not located a good pinto engine to replace the tired one in my newly purchased first transit

but I am watching a couple on Ebay
Whilst waiting I have decided to press on with the rot problems

My first action has been to purchase two new rear quarter panels from Beevers, which arrived today

Now I am planning the task ahead. I offered the panels up this evening and realised I will have to cut out the existing panels. Now what is the best way to separate the seams ? I assume the panel is fixed with spot welds, is it better to drill out these spot welds or simply go mental with the grinder
When affixing the new panels, are they better spot welded into place or continuously welded along all seams ? I do have the use of the neighbours Mig welder

And I do own my own Arc welder

I also have some college training in welding albeit a long time ago, and not on motors
Your kind advice please gentlemen.
Regards
Phil