360 truck motor

If its an 89 -360 it should be an LA style roller cam engine - gives you more options later on for upgrades - like a roller cam. no difference in 4bl/2bl - pistons are ±.080" in the hole. With your J heads @ ±72cc it will be a bit low on compression but still a good deal to start with.
I used a 91-360 for my stroker build - its a good base to start.
need any info pm me.