It's all coming back to me now.
That was the B4 boxed car.
http://www.oople.com/rc/photos/kiddy.../OOP_2403.html
http://www.oople.com/rc/photos/kiddy.../OOP_2397.html
http://www.oople.com/rc/photos/kiddy.../OOP_2399.html
I drilled out the BJ4 rear toe brace and fitted the stand off posts for the rear camber link brace through it.
JC's design allows the standoffs to mount behind the BJ4 rear toe brace flat on the chassis.