Fuel tank removal

Well done for getting the tank back in. Will you have to now do the same process for your Jaguar's tank(s) ?

The Jag tanks are steel. There is a bit involved in getting them out, But they are a known quantity, though that have an odd construction in that the joint seam is inn a vertical orientation, so and water tends to want to get trapped in the seam and rust. there is a solution once out they can be chemically cleaned and a sealing goop can be applied inside that prevents any water that might get in from getting to the seam. Of course the horizontal mounting of the twin fuel filler necks allows for the possibility of water to get in when the drain holes get blocked, but as I been around the old XJ6s and XJ12s for most of my life I know about this, so I keep those drain tubes clear. this horizontal fuel filler problem is also shared with my Triumph TR7.

Hey. What are the chances that you have a photo or maybe the measurements of the bolts holding the sheet bulkhead cover? It has 22 bolts and several nuts. I had my removed several years ago and now back to putting the car other but can't find the correct bolts....

Mainly M6 I think, going by  my vague memory

The Scarlet Fever Pages list “22 10mm bolts and an additional pair of 10 mm nuts onto threaded studs”

10mm seem awfully large for such a job or is 10mm the size of the bolt head, in which case they are actually 6mm bolts as I suggested .
For a 6mm bolt you normally use a 10mm spanner! we can blame the Amercians for this confusing situation , even though they neither understand or use metric.
It goes back to the old days when bolts were Whitworth or British Standard and the sizes of the spanners were marked with the actual bolt size not the size of the head which of course is larger. This confused the Americans, so they came up with a different system for marking the spanners (wrenches), sometimes marked on the spanner  as AF (Across flat) for instance you would use a 3/8" spanner on a 1/4" bolt this became to norm over time and when metric system came into use it was adopted.
Now everyone is confused!

There is much more to this but this will do for now!

I’m with Our Man in the Antipodes, not only with the thread size but with the rest of the analysis.
I suspect given time our esteemed author would cover screw cutting lathes, Mr Whitworth thread analysis & his diameter/pitch/form & head size.
That however is probably enough for this hour on a day when faceless men have been arseing around with the clock.
M