1988 5.2 which intake port size?

good
pull the valve cover and get the number off the head you could have the later heads with the better combustion chamber
Is 88 a hyd roller cam?
do the timing chain
small port heads will work fine in your truck as a truck
the large port heads drop the compression and you have to rev it up to get the flow back
large port will make more top end power but less grunt torque
be happy