Absolutely get the heads/valves done!
You should go to the Kohler website and download a free service manual.
I always use a brush type hone to deglaze/condition the bore. But you also need to check for excessive wear.
If you've done v-8s etc, then you know what ya gotta do.
Get the service manual.
It ain't rocket science!
'Course if yer house has more wheels than yer truck...
" Old age ain't for sissies "