difference between motors van vs truck..motor swap in progress

[Mr.Vic]

i have a 92 chevy 1500 2wd, 350, 700r4 the motor is now dead. i picked up a 305 that turns out to be from a 1991 van and i am partway through swapping the 2 motors.the 350 isa almost out, but I am noticing some differences in where the plugs and connectors; the 305 is missing some the 350 has 350 has a 3 prong plug looks like OoO connection by the oil filter and the 305 doesn't have it. is that the knock sensor?

has anyone swapped in a motor from a van without any troubles? any help is appreciated, i have't done a motor swap before so i am learning as i go, but iu have done a fair amount of research on it already.

thanks!