I took my motor out of my 03 rev 600ho today.. the rest is a long story but i haven't even looked at the bottom end yet but since i have it out i thought i myswell do the crank seals. Can you access the cranks seals fairly easily. How do you get to them.

my theory is "if it isnt broke, dont fix it"    if they look fine, and seem to be leak free i wouldnt change them out, however if the  rods are loose change the bearings!   this will prevent a very expensive fix!  ( voice of experience)

Only way you can really access the seals is to split the case and then IMHO you should replace the seals with new ones as their cost isn't worth the cost of the problem they can cause.

as SJ said, "if it isn't broke, don't fix it" when it comes to crank seals and splitting your case all together.

What kind of mileage is on the sled?

The outer seals you can replace but the inner seals are built into the bearings. Also depends on mileage and how it blew up.