Just assembled the bottom end of the 350K0 and on moving on to the top end, couldn't get the cam end bearing caps to tighten without trapping the rocker spindles (combined concentric tappit adjusters shafts) - they are free until I tighten the screws that hold the caps. Started doubting myself that I'd mixed up the (labelled and bagged) rocker arms/shafts but after much trying of different things, I measured the thickness of an old gasket and compared it to the new gasket. The old was 1.00mm and the new was .5mm! Hence the cam end covers 'squeeze' the camshaft and rocker shaft (including the genuine Honda O rings on the end of the rocker shaft) in by approx. 1.00mm - doubled up the 2 gaskets onto one end and tightened and rockers free.
The gasket set was advertised as an NE' brand but another make was sent - 'Vertex by Windrosa' - (bought from Brooks Barn on ebay as cheaper than NE brand advertised on DS website) - just thought set must be an equivelant. I have messaged them but no response yet. Genuine Honda individual gaskets are discontinued (according to DS website) and so ordered some 1.2mm and 1.00mm gasket material and will make some.
I know we're mostly Fours on here but thought it was worth warning members just in case.