Thanks very much for all your help.
I've also dug a little further into the batteries I've been using for 10yrs.
No. 1 is a 90AH 670CCA Halfords special
No. 2 is a 70AH 500CCA Delphi.
Both of these have started the engine in the past, so that lowers my expectations, I'm going to concentrate on CCA as that's what starting the engine needs, and go for @780CCA, which normally runs out at @70-80AH.
As has been mentioned my old tech EFI 200 doesn't have a lot to keep going once running, just a car type fuel pump, so I'll be OK especially as the old Delphi managed.
I've also discovered that both the batteries are type 096R, which is normally associated with American vehicles and the +ve and -ve terminals are the other way round to UK 096's.
As you can imagine it's harder to get hold of 096Rs and they are slightly more expensive, luckily I can rearrange my cables enough to swap to 096s.
780CCA is at the top end of what's available at a reasonable price in 096 size, but Varta and Exide both do one at @£60.
Need to spend some time finding them as cheap as possible now, or even take a trip to the breakers.
RIBBED For extra pleasure.
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