just finished the croix de fer ti gravel build. Got some 40c WTB cross boss on her and still plenty of room for a set of small mudguards. anyone got any options for some low profile non-raceblade sized guards

Anything by SKS, they do most sizes in either chromoplastics of blumells.

I have wide SKS mudguards on my Trek crossrip work great.

+1 for SKS.

Anything else probably not worthy spending money.

Got Chromoplstics on my Plug 3, working admirably.

Cheers!
I.

Biggest bloody SKS you can fit

As above. Be prepared to find a long bolt and spacer tube to clear the front calliper though.

No necessary.

With good pliers and a bit of fiddling you can bend stays to by-pass caliper.

Not mine handiwork, pulled from interweb…

Cheers!
I.

Got 45mm blumells on my Grade and they are great, might be snug over 40c though