Hi Tom, welcome to the asylum! We're all crazy here, but it's a good crazy
For starters, you might like to browse through my PDF collection at
https://drive.google.com/drive/folders/0B2H2NJt34OffMDVmOTZlZWItYTcyMy00ZDhkLTliOWEtOWU1OWRhNDZhYmRl
Much of it doesn't apply to TR3, but there are a few good documents in there. I particularly recommend the factory workshop manual, spare parts catalogue, and "TR3 Practical Hints 3rd ed", which is effectively the owner's manual for 1957. (The 6th edition is also there, but more appropriate for 1960 and later.) I suggest downloading a copy of anything you are interested in; but check back from time to time as I do try to improve them with notes, missing diagrams and so on.
Of course, feel free to ask any questions you have over on the Triumphs forum. I just like to read through what the factory had to say.
We love pictures, especially of works in progress, so post early and post often.
One more little tip, it's nice if you can add your commission number to your signature. I for one find it hard to remember which person has which car (heck, I do good to remember where I left my hat!) and a lot of details changed at various times.