I am trying to figure out if a Syrac Ordnance clamp on style gas block will fit under a Larue handguard. I spoke with a guy at Larue and he said that most clamp ons will not but in comparing it with the set screw version it looks like the dimensions are very similar. Anyone else had an issue with this or can give me some insight. Thanks!

I have to imagine it would fit.  I have 2 Syrac Gen 2 clamp-on blocks and they are very low profile.  One is under a Troy M-Lok rail the the other is under an ALG EMR V2.  They both fit with plenty of clearance.

The syrac set screw gas blocks are only slightly larger than a standard low-profile gas block from Rainier Arms or VLTOR.

Last time I looked Syrac had dimensions on their website under each product listing.

I would compare the Syrac's specifications to the SLR Sentry 7 adjustable gas block with set screws. The diagram is on their product page. I have the SLR and a LaRue rail. What I found out is that you can't slip the rail over the gas block with it already installed. The ass end of the rail opening is too small at least for the SLR. What member Apparition suggested (which worked) is to loosely install the rail so it can be moved around the barrel. Install the gas block after the rail goes on and then move it around so you can access the set screws. After the gas block is in place, move the rail back and tighten it down to the nut. Problem solved.