are the 5.3 862 casting heads worth port and polishing?

i also have a set of ls6 valves int and ext, are they bigger than the 862 heads valves?

i currently have a set 862 heads, ls6 yellow springs and valves, locks, retainers, seals....

ive been thinkin bout port and polishing the heads and putting the ls6 valves in them if it is worth it.

just looking for some guidance