Ok, I tried with partitions at 3, 4, and 8

> > disklabel: ioctl DIOCWDINFO: Label magic number or checksum is wrong!

> In your label the numbers do not match: 64 * 8 * 606 != 310352.
> Using size 310272 should work.
>

I changed that value also

It still gives me an error,
>disklabel -R /dev/sd1 MCA
sd1: no disk label
disklabel: ioctl DIOCWDINFO: Label magic number or checksum is wrong!
(disklabel or kernel is out of date?)

Any other ideas?

The drive has a switch on it, with 2 positions, one for direct access type,
and the other for optical memory device. I've tried with switch at both
settings.
Other switches are for termination, auto-spindle stop, and write
verification.
Thanks for your help.
    John