400 low buck dont give a

hey guys quick question for you guys that have done the big block swap from small small block....I have the transdapt mounts to replace the small block ...I was going to try to install the motor and trans in 1pc but im not ready on the trans and would like to know if it would be that much harder to install the trans later then it would if the car was still small block....this way I can go ahead and install the motor and figure out the mounts and header deal....I plan to hit it a little this weekend ..as far as the trans goes I need a few other things before I can move forward with it so its on hold for right now.....so if anybody used the same mounts please sure your thoughts and does and donts..thanks guys