02 Frontier Engine Swap

I have a 2002 Frontier 5-speed manual that the engine blew. I bought a used engine from a 2002 Frontier automatic. There was just one little problem with this. The auto engine does not use a bilot bearing for the transmission input shaft. I tried to install the pilot bearing of the manual transmission onto the rear engine but it won't fit. Bearing is too big. So what I have now it that the input shaft of the transmission is fitting loosely onto the rear main.
Does anyone have an input into this? I have been stuck on this for a while now and need this truck back up for hunting season coming up soon. I'm beginning to think it may be ok to just install it as it is, with no bearing. Thanks in advance.