As said being studied on how a longrifle is assembled is a big plus. Another less expensive, but good book is Dixon's.
Link
The classic CVA Kentucky type like yours has some quirks to overcome. These quirks may actually be more complex than say a more authentic parts set. Also the instructions are vague on purpose, it requires some problem solving and as said, prior knowledge on how these guns go together helps tremendously.
Simply put, even a pro can't throw one of these together without thought and care.
I've never built one of these but I have owned and rebuilt one.
First and foremost the breech and tang of the barrel as does the nose cap, has to be fit and set correctly to the stock before the tenons. This is where the two piece stock can complicate it some.
It's my opinion that the two piece stock will have to be assembled correctly to fit the breech and the nose cap. If I'm not mistaken the breech and the nosecap are the points that are "known" on this design. In Other words these two points, The tang screw and the two nose cap screws hold the front and the rear of the barrel to the stock.
The tenons and lug location is "unknown" so these will need to be fit after the nose and tang.
These have to be done correctly.
Here we get into the "quirks" of this design, you need to test fit to make sure everything will line up for later assembly. Once everything is aligned
without the barrel tenons or lugs then you can install the tenon or lugs. You may need to screw down the tang and screw down the cap to confirm fit. You may need to work on the barrel channel as well as the nose cap and tang inlets. It should be tight but not to tight as to distort the wood when you install the barrel.
The building books mention in letting black, lipstick or even wet magic marker ink to confirm fit. You have know what it's telling you...that just too much for this post.
You are satisfied in how the barrel sits in the barrel channel of the stock and the fore and aft mounting points are correct, now you fit the lugs.
You drive the lug into the bottom of the barrel, just like you do your sights...on the top. You need a file, punch, light hammer and a drift preferably brass to do this. Go slow in fitting the lugs, these will be practice for the sights. If you file too much away making the lug loose, you should be able to lightly tighten up the dovetail with a hammer. The thing is to try and fit try and fit and not loosen the dove tail too much. Rule of thumb....modify the cheapest part to fit that being the lug or tenon and not the barrel dovetail...but it may need de burring just to clean it up. It should be pretty close.
One you have a lug in the bottom of the barrel, fit it to your stock. These stocks already have hole for it but still the fit may not be correct, if it's off recheck to make sure everything is right, then work on the hole for the lug. When fit do the same for the next lug.
With barrel fit in the stock and the lugs fit correctly, now you can mark for your pins.
Measure and find the bottom of the barrel and mark that on the side of the stock. Mark the length of the lug also on the side of the stock.
By careful measuring and marking on the side of the stock, you are determining where to drill for the pins. You may decide to align both the front and rear pin holes with each other, if so measure both and use a straight edge and tweak the marks where both align on the same plane. Once you have that all figured out, mark a cross and this will be your pin hole.
A drill press is nice but you can drill this with a hand drill if you are very careful.
Some will drill the holes on the marks without the barrel in the channel. After the holes are drilled, they replace the barrel and drill through the lugs.
Some will drill with a small bit then use a larger one in case of a mistake.
Some will drill from both sides meeting in the middle.
I for one would rather drill from one side. You need to keep the drill as straight as you can, you may need to practice on scrap first.
good luck
