Good News for 20 years in a garage 1977 XJ12L

First of all, my thanks to the many people willing to help a first time Jag owner navigate the minefield that is a neglected V-12. I am sure to beg for advice in the future.
Having read about frozen distributors and general mistreatment of them and also knowing the timing was off I decided to remove it . It was a brown bowl of yuck. After a bit of elbow grease and brake cleaning fluid, I had a shiny distributor with clean weights,. I also replaced the red wire from the amplifier as it had been nibbled on by rodents. I centered the screws with the springs and also centered the vernier adjustment.
Back in went the distributor, after a few drops of oil had it spinning very freely, and I put the timing mark onto the correct spot.
As I was replacing the plug wires I noticed that more then a few had backed up into the boot. Fixed that. It was now dark and if it didn’t start I was going to go to bed still depressed. Should I just wait til tomorrow?
What the heck! I turned the key and after a few seconds it caught. A few more seconds it started. It then ran very poorly, for twenty seconds or so, as all the previous attempts at starting were being burned away. But then it smoothed out, then it properly revved very nicely to as high as I wanted to take it. No backfires or hiccups. Wow! With the vacuum advance still disconnected! I turned it off and came back 5 minutes later . Instant start. Next day 35 degrees out . Instant start.
The AAV does alter the idle so I am hopeful when I install the water pump and can warm up the engine I will be able to get it to darn near perfect.
I was determined to not let it beat me. Thanks for the help again.
Since I have replaced the shocks,brake calipers, and the transmission, I can now move onto what I knew the car needed when I bought it. A water pump. A ‘simple fix’ I said to myself when I bought the car. Somehow I am now thinking that unlikely . We will see.
Thanks again Jag Lovers