Got the piston kit (solid, .750) in last week after being backordered on Brownells for a while.

Upper build:

Surefire Warcomp
10.5" Faxon chrome lined 5R barrel (she's nice and thick; Rainier exclusive)
Bootleg upper
Sharps Relia-Bolt in NP3 Plus
Bootleg 9" handguard

Lower:
PWS MK1 Mod 2 complete lower
Carbine buffer weight

The bleed off (4.5 turns out from closed) didn't have enough juice to lock back an H2 buffer. It became tuneable when an H or carbine weight buffer was introduced. I honestly couldn't get a difference recoil wise between the two so I stuck with the carbine weight and fine tuned it from there. I’m currently at 26 clicks out from fully closed
The rifle runs great and no issues were seen function wise. For the brass chasers, the brass was chucking around the 3:30-4 o'clock area. The bleed off however is getting things a bit dirty but it's whatever. I'm noticing residue on the top of the barrel and obviously around the muzzle device.

Fit wise the gas block/piston housing BARELY clears the upper channel in the Bootleg handguard. The pictures below make it seem like it has room but the shadows in the pic are deceiving. I barely clears.. Maybe by a *unts hair.

Fine looking stick!!  And yeah, that is barely clearing alright!

Does the gas port diameter matter when converting from DI to Piston?

It shouldn't as the superlative system is an adjustable gas block so you would be making final adjustments to get it running as smooth (or rough) as you want it.