The inlet manifolds are different, so yes, you will need them. Your best bet would be MC21 carbs/inlets/reed blocks/HRC rectifiers.
One side of the inlet manifold is rubberised, so you only need a gasket between the reed cages and the crankcase (so long as the manifold is in good condition!), and you can make the gasket out of gasket paper from a bike/car parts shop.
Most gaskets/parts can be bought in the UK from any Honda dealer but use our Online Parts Manual to find the relevant numbers (MC16 section is nearly complete, just ask if you can't get the numbers you need) else 99.9% of Honda shops will laugh you out of the store without them!! :D
Many MC16 parts will be unavailable new now. But alternatives can often be used, and there are still sources out there for second-hand stuff. Try TYGA Performance (on Links page) for spares.
Jeff:
I didn't drop any names!!
Just in case you didn't want to own up!!
Andy.
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