Joseph, I have recently completed a 68 restoration and engine rebuild so let me offer some opinions. There is much satisfaction in completing such an effort although that joy may be hard to maintain sometimes.
I found the toughest task to be engine removal and installation, especially removing the clutch slave cylinder and the reaction plate. Both are the subject of several posts in the past, read them. I used the Jaguar shop manual for directions but the extra input from forum members really helped. Two tips: first, have a good hoist that allows lifting the heavy engine with the boom fully extended and second, raise the car body a few inches; that will allow you to tilt the engine more vertically which I think would help clearances. I did not do that but wish I had.
If you have a decent engine stand, disassembly is is straightforward; I enjoyed it, I had difficulty because three pistons were frozen but that is not your situation. My engine did not need machining or valve guide replacement which made it possible to DIY everything. If you perform a compression check on yours before beginning you can set your expectations of what is coming.
Assuming you do this, plan to build or buy a sturdy test stand so you can run and check the engine before reinstalling it. It is an effort to supply gas and cooling but it is worth it. Never again will you enjoy such easy access.
Pardon my running on but I enjoy the subject. I hope you are encouraged.
Bill Braun