If I understand correctly, you wish to mount options on your tube, rather than switch to a railed platform.

Tactical and varminter, two completely different styles of gun.

You have the smooth free float tube/handguard,no rails.
Tactical handguards have rails, by which you can mount your tactical accerssories.

If you desire to mount items on your gun, you should switch to the railed handguard.

The only option you have(that I have seen) to mount items on your gun, without switching hanguards(which requires removing the barrel in most cases) is to replace your front gas block(as long as it is exposed, and not a lo-pro thats under your tube) with a 4 rail DPMS or other brand.

I have three ar's right now. An Oly Arms standard A2 carbine, an Oly Arms A3 20'' with full length freefloat 4 rail, and a YHM A3 with Spectre length 4-rail, and White Oak Amament 16" stainless bull barrel.

I bought the A2, knowing full well options are greatly limited, and the A3' were for my vertical grips, lights, bi-pods, scopes, etc...

Either replace you gasblock, your handguard or your gun, depending on what suits your needs most.