Aye Oldvelo,
Sorry not my neck of the woods, but I'd have thought the info on this site would give you plenty of basic background as the FX and SLR are both Spanish built varients of the original NX Dominator so far as I am aware, I stand to be corrected by Jethro, Pat et al, they being owners of these beasties.
Here's a link to some background chit chat, which may give confort:
Background_chit_chatLink to site where manuals etc are downloadable:
DOMINATOR_OWNERS/WORKSHOP_MANUALSThere is also this download site for which a small payment USD is required:
US$_DOWNLOAD_SITE_FOR_MANUALSBoth Haynes and Clymer do manuals for the XL500/600 and XR600/650 4-valve singles.
If I see my Honda dealer acquaintance, I shall make enquiries, but this may be a wee while and if you turn up a suitable alternative meantime, use it.
I hope this helps.
My regards, Bill.