Hi Chris and welcome.
You have already done an incredible job -- you found a vet who is informed about Lantus and even better, supports home testing, you've switched all of your kitties to low carb, canned food, you've familiarized yourself with some/most of the information here, and you are posting. Those are some of the bigger hurdles.
The front end of this learning curve is huge. Please don't hesitate to ask question. There are several very experienced Lantus/Levemir users here such as Jill, Libby, Cassandra, CD, and Heather one of whom tries to be here so there is guidance almost 24/7. There are others of us who haven't been around as long and do our best to make sure there's someone around who can respond to questions and get a pair or two of experienced eyes to your condo (that's what we call your thread for the day) if you have a question or concern we can't easily answer. There are also some very experienced people who drop by and lend a hand but on a less frequent basis.
You asked a question about whether to stick with 1.0 or 0.5 units of insulin. One means of gauging the initial dose is based on your cat's ideal weight. If you know Mally's ideal weight we can give you an approximate dose -- although, it's usually in the neighborhood of 1.0 unit. Ultimately, what your starting dose is, is your decision. One thing to keep in mind is that within the next few days you will be dosing twice a day. You need to be comfortable giving whatever the amount is, twice a day. The consistency is important. You may want to give your vet a call and let him know how Mally did on this dose today. It's also possible that Mally's numbers may be a bit higher after the 63. (There is a phenomenon called "rebound" whereby the liver will dump glucose into the system because it panics when a very normal number like a 63 occurs. The liver isn't used to having a BG level in the normal ranges so it takes action.)
The 63 is a very desirable number. The
Tight Regulation Protocol that we use to guide dosing has very strong research to support its use. One way to reduce your cat's insulin dose and eventually reach remission/regulation is to have numbers drop below 50. This is not dangerous and is easily steered by the use of both low and/or high carb food. (So stock up on the 18% carb food with gravy!) Research would never see the light of day if it was putting a kitty's life in jeopardy and none of us would be here if this protocol didn't work.
Please post every day. Read our condos and study everyone's spreadsheets. And most importantly, ask questions. We'll do our best to answer. And again, welcome. This is an incredible place with incredible people who really do understand.