Thanks to all who have helped in the SIRS threats, barrel twist, etc.  

In the interest of saving money, I'm trying to determine what I should realistily order from Bushaster when I have them build my complete uppers.  I still like  the SIRS system, but a reality check makes me think twice.

I have decided to buy M4 14.5" barrels and have phantom perminantly attached for legality of having a 16" total barrel.   I have also decided to purchase an Aimpoint M2 for it, along with an ARMS 22M68 for mounting.  The question is... with the scope I have picked, coupled with the fact that CA has banned night vision scopes, am I better off just ordering an A3 upper receiver with an ARMS 38 BUIS/rail for the top of the A3.  Should l go with M4 handguards?  Is spending the cash on the SIRS a waste of money, or spending the cash on any forward rail system even justified for my "setup"?  I  like the Surefire grip/lighting setups, but $500 for a flashlight/grip is too outrageous.   I have a green light for this "purchase" from the spouse, but don't want to be too greedy...  Should I plan on mounting the M2 scope on top of the receiver, or does placing it on a forward rail make it more easier to use?

Sorry to keep on with the qyestions, but CA has few shops that carry AR stuff now, let alone stock any parts.....

Well, let's start from the beginning. Since you are going with an M4-profile barrel, might as well splurge on the M4 handguards too. Since you will not be using a night vision optic, you might as well go with the aimpoint ML2 instead of the M2 in order to save a few bucks. The only difference between the two optics is that the M2 is nightvision compatible, other than that they are identical. I'd go with an ARMS #40 BUIS. If you use the ARMS #45 SIR, you won't need a spacer to cowitness with the ARMS #22M68 mount. If you choose not to go with the SIR, then get a spacer. I recommend the cantilever spacer. I would mount the Aimpoint as far forward on the upper receiver's rail as possible instead of forward on the SIR or whatever rail system you choose.

Quoted: Should l go with M4 handguards?

If not a rail system

Is spending the cash on the SIRS a waste of money, or spending the cash on any forward rail system even justified for my "setup"?

Opinions vary widely on rail systems, but I feel there are better options than SIR's.

WTF, the banned NV optics ?

Now I would like to know....And this is the first I have heard of Commie-fornia having a ban on NV. If so what kind of ban? Just rifle mounted NV scopes? Or all NV devices, like PVS7 goggles? If its just rifle mounted scopes I suggest you get a pair of PVS7's and get the NV compatible red dot site. That's what I have done anyhow.

Ca banned night vision weapons sights with IR sources, NV sights that are totally starlight with no IR source are in an iffy realm because the night vision "sniper scope" wording seems to be interested more in the sights that had IR illumination.

It is strangely worded.    From what I can tell night vision binocs and monoculars are okay but it would be safest to stay away from mounting it on a rifle.