While certainly a nicely detailed model straight from the box, Hornby's Seacow is layout-hostile if you use any couplings other than the supplied tension-locks. Even my standard fall-back option (Smiths Instanter) proved difficult as the plastic bar that spings the buffers prevents easy insertion of the coupling hook.
In the end I snipped off most of the hook's stem and slotted the remainder, then bent the two short prongs in opposite directions so the coupling was effectively a T-shape. I surgically removed the chunk of black plastic nearest the buffer beam that holds the spring-bar in place, but left the furthest one intact. Then I slotted the bufferbeam from underneath with the end of a razor saw in my usual fashion, and widened/bevelled the back of the slot to take the hook. After all this unwanted faffing around, the coupling was glued in from underneath, effectively using it's tail to replace the chunk of black plastic removed.
This method retains the functionality of the Hornby buffers if you don't go too mad with the glue, but is somewhat fiddly as care is needed working next to so many fragile parts - I doubt if I'll do many wagons this way.
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