New member, first Jaguar, intro and looking for advice

One of the very first things to consider is getting a 140 shop manual and getting familiar with the major systems on the car. All the advice above is good but assumes you have a basic understanding of the car and it’s components.

So much valuable information here.
It’ll take me weeks to fully internalize and understand all this feedback, and I appreciate every single word!
My father in law gave me the car over a year ago and it took me over a year to bring it home - I had to make space in my small garage and it took much longer than I had planned.
To prepare I have been studying three books:
Original Jaguar XK - Philip Porter
Jaguar XK DIY - Bob Exelby
Mark VII and XK 120 Service Manual + Supplements

They have been helpful to look through, but it’s hasn’t been until I now that am digging through the actual car that I can start appreciating the specifics of what I read, and compare parts with photos and descriptions, etc.
I also have a book called XK120 Explored by Bernard Viart on order, I saw a few photos from that book and it looks as useful as it looks beautiful.

Taking the valance off looks like a great idea, and thanks for the warning about the bonnet - I will leave that in place. Looking at the valance on the passenger side (by the carbs) it looks like someone has nibbled out a good chunk of the panel - maybe to make room to work on something? I’ll try to post a photo of that.
I will definitely document every piece I remove before and I will post some photos of the car as it is, and join the local chapter of the Jaguar club too - and once things open up more (knock knock) I can start attending meetups etc. Plus, if I were to run into something that I can’t fix, or don’t want to get into (maybe the clutch that may or may not be bad, or if I don’t feel 100% about the breaks) then I have a jaguar specialist here in town that I can take it to to get quality work done. Trading money for skill & comfort level as it were - but I worry too much about that - I don’t have a fixed timeline or a fixed budget so things will take the time they take.

Thanks all!
C