I see the 6 Volt type 421 batteries used for for the TA and TB (and early MGBs) are now running at up to about 205 UK Pounds a pair.
Far better would be the current compact high power B36 12 Volt battery, which has the same footprint as the 421, drops right into the chassis battery tray, and only costs about 50 UK Pounds, including delivery.
It's easy to fit with just a bit of rerouting of the battery terminal cables of course.
It also frees up the other battery area so you can fit a neat useful toobox there.
I've used a VARTA BLUE DYNAMIC BATTERY TypeB36 on the TA and TB and other cars, they have been in about 4 years plus and never a problem, even when starting from cold in sub zero temperatures.
I've used the Vartas (no connection to them) and doubtless there are other makes.
All Best,
Clive
Oxford, UK.
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