Any advice on fairing repair? Got some fine cracks....

The panels are AES (Acrylonitrile Ethylene Styrene) rather than ABS (Butyl) so may solvent weld with acetone if the crack is fine and the edges are in good contact.

Plastex works well. Chase out the back of the crack and fill with the repair. I've remade mounting lugs and screw bosses and they have held up so far!

Another vote for plastex, fixed my seat mount lug very well

Plastex gets the thumbs up from me as well, Main seat lug repaired like new!