Paralysis by analysis, and the fix

Since at least yesterday when I dug out my selected patterns, I have done nothing other than read the directions to Simplicity 2562 ... paralyzed by what is probably overthinking. 

Like most of my projects, this is my first go-round with this pattern, and I only have 2.75 yards of my black mystery bundle fabric that I intend to use, which is the amount the back of the envelope says I need for view B, the noncuff version.  I don't have enough to do cuffs.  I haven't tried prewashing said mystery fabric, mainly because I'm still not sure what it is exactly.  I do know it is not a synthetic.

I was quite congested when I burn tested it originally, so have no idea what it smells like.  It did catch fire, but the flame sort of fizzled out on its own, so it may have wool in it.

With no room for error in cutting, I have decided to do a wearable mockup first ... and have finally made up my indecisive mind on what to use for that: a midweight drapey denim that I don't recall when I actually bought, but I have about 3 yards of it and it will make nice mostly-dressy jeans slacks.

Since this is denim, I'll probably slap patch pockets on the back and use jeans buttons instead of pants hook closure thingies, but this will help me nail down the fit idea so I can adjust the pattern pieces to use the least amount of fabric on the black.

New techniques for this project: shaped waistband and a real fly (as opposed to the mock fly I did on my gaucho pants).  Now I just need to find the sewing motivation to move around, as my back and knees still feel stiff from the road trip.