I am not familiar with that exact system, but I have comments on what works for me. Try to find directions from the manufacturer here, or from them directly.
I line-up everything off the bike, to simulate what pieces are supposed to go where.
The studs at the front, I wire-brush those and I use new nuts, with a bit of never-seize.
I start at the front, and work towards the back. Loosely-fit the tubes together Try to make everything loosely positioned and linked-together. Start the nuts, but don't tighten anything until all the pieces have been fitted.
Now, you will probably see where some pieces need to be 'worked' to allow for proper placement of one part to another part. In some instances, like the Kerker 4/1, one side of the centerstand will need to be removed, and the other ground-off or bent somewhat.
Start gradually-tightening everything, a bit at a time, and see what needs to be manipulated to best-align the pieces. The tubing should start to resemble a complete system as you gradually tighten fasteners.
As things now are approaching their final positions, you may find it necessary to loosen and re-position some parts to get the maximum points of insertion, and the ability to draw-up tight all fasteners.
Once you think you're done, I usually grab each section of tubing, and give it a good shake, twisting it and pushing/pulling it, to see if anything needs a bit of adjustment. You may find that some systems may not seat all the way-into a receiving piece, to get maximum insertion someplace-else. Yes, very-much a puzzle, one that you are almost-finished with.
Let's say that you have it all assembled. You're OK with points of insertion, OK with tightening the fasteners, and any hangers are where they need to be to support the system. Start it up, and see if you have any obvious leaks. After a heat-cool cycle, you can check for loosened fittings, you might need to do that several times, until every fastener stays tight after riding.
Make sure that any fasteners are clean of rust/corrosion, and you should replace any fasteners which are suspect for structural integrity. A word of caution about using stainless-steel fasteners: SS nuts often can cause galling when they're used. The nut becomes harder to turn. DO NOT attempt to run-down that 'sticky' nut! It may seize, It may snap-off a stud! You could attempt to re-thread it, with a tap, but I just buy extras and throw the galling ones away.
