I think type A is 254/260 In/Ex for RB25 and type B is 260/260.
When I say the rods are the same I mean they are exactly the same. From the same place, same time, same material etc.
I think if you put a GTR crank in you need different pistons too. Just put a collar on the RB25 crank and you will be right. There's not enough difference to matter.
Installed some new gauges on the weekend.
Also finished the front bar. It's just hanging on there at the moment.