s-10 chassis swap cab mount ?

[KevinsKustoms]

Ok, so I have been fabricating my cab mounts for my s-10 chassis swap, basiclly going from the blueprint from jeffs51 but have ran into something I'm not sure about. I need to know where the hole for the cab bushings should be located on the top plate of the mount. should it be centered or offset ? I am building my mounts out of some metal that we had setting around the shop and its pretty thick(overkill) but it was free! I just didn't want to have to drill the holes in the wrong spot and have to start all over.