BSA A7 Iron Head, fitting bottom valve spring cups

[A7restore]

My original head was broken so I bought a replacement head (part no. 67-381) which did not have the bottom valve sping cups fitted (part no 67-0033). Having procured a new set I find that they will not fit over the valve guides Do they have to be heated prior to fitting. Measuring, to the best of my abilities, the guides have an exterior diameter of 15.69 mm and the spring cups have an interior diameter of 15.47 mm  a difference of about  0.22 mm. Any advice would be gratefully received. Thank you

[Rex]

Break out the round file...

[berger]

break out the small grinding wheel they are hard

[BigJim]

They sure are. Took me ages with a file! One way of keeping warm in he garage.

[muskrat]

G'day A7restore.
As stated they are hardened. A dremel & stone is the best option, even better if one in a lathe.
Funny your the second to have this problem recently. There must be a supplier of guides that have a larger o d.
Cheers

[berger]

big jim one way of keeping warm and destroying a file

[BigJim]

Oh dear!