I put R31 control arms in my KE55 (cause I had them lying around), should be the same as KE70 yeah? It was a pretty dodgy job, if you're not a ghetto fix sort of guy I wouldn't suggest it.....
Anywho KE55's have 10mm or so bolt for the crossmember -> control arm
R31's have a bolt with a 10mm or so thread but a 14mm or so body, so I drilled the rear holes of my crossmember out with some drillbit I had lying around which happened to be the right size (can't remember what size but about 14mm). Like I said the thread is the same size so you only have to drill out one hole for each side. By some chance the bolts were the perfect length and the bushes the correct width so it turned out pretty damn snug in the end.
The second problem is the ball joints, the R31 has giant huge ʞ©$ɟ-off indestructible bolts for the ball joins -The tapers will NOT fit stock KE55 steering arms, but since they're so giant huge ʞ©$ɟ-off indestructible you can just bolt them in anyway and get heaps sick roll centers.
~I just read you're using s13 hubs (durr) so NM this part, but *THEMOREYOUKNOW!*~
My stock KE55 tie rods had more than enough adjustment to be used with the longer control arms because steering boxes kick arse, since you have a homosexual rack I don't know if you'll have the same luck.
Caster rod holes I redrilled heaps futher out, which allowed me to wind in dickloads of castor with stock rods -I can suggest this!
Here's an illustration I prepared in super special christmas colours: