You can buy
oil filter adaptors to suit the LS1. Unfortunately most seem to make it difficult to use AN swivel fittings with nice bends to reduce restriction. They end up hanging below the sump where they are easily snagged (not a good thing to have happen). It can also be difficult to get larger line sizes connected to them.
I came up with this setup shown on an LS2 Corvette sump which is significantly lower profile than the Commodore sump. These are AN #10 fittings.
Here's the inside showing the O ring seal etc
I reckon you would be surprised at the
oil temps in the Commodore towing the van. I don't think they are shown on any gauge nor are they monitored by the ECU. Also pulling it up a hill won't be done with your foot flat to the boards on and off for an hour as you would circulating a track.
Cheers