fitted new varta battery

fitted a new varta battery,  blue dynamic, f17.....12volts-80amps hr, with a cold cranking amps of 740.  so I started with my very long extension  lead and placed it on my little cars battery first, then clamped the + and - leads on the jag. making sure that I closed the alarm switch on the bonnet so it did not leave a open circuit. this was done by a piece of wood and a adjustable clamp to close the switch. so with that all done I removed the battery and done a test with my multimeter  that 12v power was still running through the jag ? "yes all was good"   then fit in place the new varta battery, connect up with the leads back onto the new battery terminals with the extension leads still attached. ( remove extension leads ) put key in jag and just check everything still works and still lights up ok....yes....turn key and the old girl bursts into life.  so I do not have to reprogram a single thing !  got my OBD reader and done a final check....and again all was good saying NO CODES.  so went for a drive, yes the baby 2,0d jag ran fantastic.