Does 18R intake fit onto 21R head?

[restorolla]

I have no idea if they're even close but does anyone know if the 18R intake manifold will fit onto the 21R cylinder head?
There seems to be a lot of aftermarket intakes, etc. avilable for the 18R but nothing much for the 21R.
Thanks, Rob.

[thechuckster]

are you talking 18RG or 18R? - if the later - then not at all.