Consider a re-power with this highly efficient crate motor:
https://www.roadandtrack.com/news/a37990530/chevy-1004-hp-crate-motor-zz632-1000/
I’m thinking about putting at least another 50-75k on my chevy van,its a 2010 with 250k miles on it now.Im off the road so i only drive maybe a thousand miles a month if that.I did 70k a year for 30 years but finally got tired of the road.
I special ordered it with the 6.2 engine I think and a 3.56 rear end for better mileage,it used to get 20 now it gets 15 but still runs pretty fast for an old van.