Trying to install them using the stock Cav rails would probably give you a more challenging install, as a Cav has a fairly flat floor since it is a FWD.... You would probably need to fabricate some adapter brackets to use the Cav rails on a Pickup/Crew, but maybe not for a Blazer/some Burbs... Now with that said, you might be able to get away with redrilling the seat frame mounts, if you were going to use 73-91 Truck rails(Some non truck Buckets will bolt directly to the truck rails no mods needed)...