If ur train has a stop at Pattambi then better get down at Pattambi and just outside the Railway Station u have the bus depot from where u will get buses to Guruvayur
From Shoranur the bus stand to Guruvayur is bit far n u have to depend on Autos.
If...
more... ur train has halts at Trichur get down at Trichur and catch the connecting train 16127 MS GUV Express from TCR @ 04:55 hrs. Bus service from TCR is better and bus stand is at walkable distance.
SRR TCR GUV is kind of triangularly located...