Whatever the pic in the ad shows, those links need to be flipped.
Rake and trail works the same for any bike.
A line straight through the steering axis to the ground, mark that spot.
Next drop a plumbob from the axle centerline and mark that spot.
The distance from the axle mark and the steering axis mark is "trail".
Axle should be behind the steering axis, thus the term "trail"
Negative trail (when the axle is in front of the steering axis) is dangerous and should be avoided.
Think about a caster on a grocery cart. it always follows the vertical steering axis.
On a car rake and trail combine for the caster part of alignment, camber being the tilt of the wheel in or out.
On a sportbike, rake is very steep and trail is around an inch, resulting in quick steering.
Most choppers have generous rake and trail numbers of 3-5" are generally acceptable.
These aren't road racers although some of us ride 'em like they were.
Most are set up for long distance high speed stability, so quick steering isn't really a priority.
There are ways to bring trail more into "handling mode" and that's have new rockers built with the axle in the proper positon, be it more forward, or up or both.
The rear leg looks a little short, causing the unloaded bind, is there a spacer under the top tree above the bearings? Could be a longer stem from a different bike, Lots of mixing and matching back in the day, hell today still for that matter...lol
As for the brake, you are linked to the right spot, but the wrong angle.
The stay should be in front of the forks in a pull configuration. You have it in a push mode so it's making suspension work where it doesn't need to.
I run mine on the right side with no problem, the mechanism is not directional, but I've always seen them on the right side.
I have the same hub with a 16" on my 750 chop, and they anchored the brake to the rocker, so when I apply front brakes the front rises. It's not correct, but I have a lot of fun on cruise nights poppin' the brake and bouncing the springer off the ground. Kinda synch up the brakes with the bounce.
Bike looks cool and once you get the forks working right ya might be suprised how easy they are to ride.
A wise man once said... build it how you want it, then learn to ride it like you own it