S13 rb20det
 

First post so be gentle.

I'm doing a rb20det conversion in my s13 (previously ca18det)
I am having problems lining the gearbox mounts up, I've got both the ca18 and a r32 gtst crossmember, rb20det mounts aswell as a gktech gearbox mount (solid billet) this is my first conversion by myself. Problem I am having is the box is sitting about 25mm to far towards the rear and I cant seem to get it any closer.

Any advice is appreciated, as I've been stuck on this for a while now.