Vee_Que Mustang 93 gt shaft is the one that matches. Alternatively if I do a clutch and flat flywheel I can supply the correct spline clutch, similar cost.
Sorry, but no - the W2RA 7003 AA Ford 6 box won't take any off-the-shelf V8 input shaft.
It uses a BTR cluster gear, 0552-077-031.
Like all BTR clusters with a "0552" part number, it has a different gear helix angle to any 23-tooth input shafts used in US boxes.
Screenshots below from BTR Service Bulletins 259 (for 6 cyl, late 1993) and 262 (V8) dated March 1994, show he part numbers. Nothing much changed with the boxes internally after this; only the extension housings and shift rods to match. 91DA means EB Ford.

Note how Ford V8 boxes with a tapered input bearing use a US-type cluster, the 1352-077-070.
The '053' cluster is used with needle roller input shafts, and that also is the same cluster as used in US listed assemblies 1352-115, 1352-188, 1352-202, and others.

053 clusters mate with 1352 085 020 [10 spline, 24 tooth] input shafts.
070 clusters mate with 1352 085 060 [10 spline, 24 tooth] input shafts.
EDIT: Unfortunately, Gear Repair Australia appear to be out of business now - although their website is live, their phone number comes back as disconnected. I'm making enquiries to another company in SA to see if they offer a similar service.