Just buy a flywheel for a 6.2 with a manual transmission.
They were available for 82-92 models of Chevy/GMC pickups, Suburban's, Blazer's and Jimmy's.
I have gotten mine at Napa, and they always had it in stock.
Just run a clutch made for the same truck as well. If it was an 83 K-5, get a flywheel and clutch for that and just confirm that the clutch has the same number of teeth as the transmission. It should.
05 2500HD CC LB LLY, 4x4, 3.73s 235/85R16's, webasto cab heater, to keep it warm.
03 Buick Rendezvous - When you average over 80 miles per day driving around, you need one of these.
85 K-5, 6.2, SM465, Rockwell T221, 1 tons, 36's. More goodies to be installed as time and money allows.
82 K20, 6.2, SM465, NP208, stock except for bed rack, snow plow, and glow plugs are on a toggle switch. It works great for plowing!
72 Postal Jeep - Yet another project