Mopar Muscle Association UK

Looks like the battery has been getting cooked every time I have driven the car, it failed to start after a week sat in the garage waiting for wheels and tyres.
I trickle charged it for a couple of days started it and checked the charging voltage......18.4 volts
Drove it to a local battery supplier to see if he had a suitable battery, he tested the old one and confirmed it to be finished.
He didn't have an 069 in stock, more arriving monday.
He said they will be about 560 CCA, I'm assuming that will work, the existing battery has no capacity information on it.
Having looked on the internet I see that a duff battery can cause a high charge voltage but it is more likely to be the voltage regulator, does this sound familiar or should I look at other things too.

I had a regulator fail. On the way to work one morning I noticed the ammeter was endstopping above 1500rpm. I had to drive the car to work and back while keeping the revs below 1500rpm. Changed the regulator when I got home and back to normal. Luckily I caught it early and the battery survived unharmed.

Thanks for that Mick.
Yes the ammeter is way over as soon as I touch the throttle, I did notice it was well over when I bought the car but thought nothing of it.
I just ordered a voltage regulator off RockAuto, here on Wednesday.