what is the favored method?  chemical or fire? I guess the best approach is buy a used manifold and new gasket, make sure its fully cleaned then swap out and sell on the manifold?  does anyone know the manifold part number on a 80bhp 1.4tdi?  is it 045129713F

Yes, best to remove it. It's not hard. Don't know the part number. Check with Skoda parts dept. Take reg no or Vin with you. Chemicals or fire risks debris going into your engine. How bad does it look from the outside? Have you looked?

its on 157K and from the service history I can see that the EGR has been cleaned 5K ago so that looks alright when I had the boost hose off to check, but as they didnt do the manifold I guess that is going to be pretty bad.  the car has little or no power so just working through all the bits that need sorting.  I would not look at cleaning on the car at all, just wondering if anyone has tried the fire method personally as it looks like it could be fun as well as quick and cheap compared to using chemicals.