Make sure both TCA's are bolted in loosely, then with a jack raise the tca/hub up and you will find it gets alot closer at one point, with a bit of swearing it will go in a lot easier at this point, if not I sometimes use a £1 ratchet strap from the cheapo shop down town to draw it in closer, works a treat, keep the bushes on the roll bar NOT in the tca to start with and it will also be easier(bigger hole), just simply push together afterwards.
If the rear arb mounts are undone so it swings loose it will also make it easier.
tabetha