Aye beezer764,
This link maybe of use:
'SRX4-6-SpecTable' You can also download the SRX600 workshop and owners manuals from this site if you wish.
My 'gut feeling' would be to end gap the rings as normal, allowing for the same ratio of end/side gap as that for the SRX6.
Pages from SRX6 manual that you need to see are 3-28 & 3-29. If you can't find them, PM me and I will attach them to my reply.
Hope this helps.
My regards, Bill.