/6 head bolt + ring and bearing suggestions please.

When I rebuilt the OE slant motor in the 68 Barracuda I went in the opposite direction.
This OE motor had cylinder bores out of spec for taper and size, the mains and rod journals were at the upper limit but not scored.
I built this engine for drag racing and wanted a ‘loose’ motor.
I took it completely down, kept bearings-pistons-rings marked so they could all go back in the same hole.
Cut the head to get the compression up to 9.5
Put in new valve seals, 340 valve springs, re used the existing valves with a back cut, cleaned up the port bowls and had new seats cut in.
Power Ported the pistons, this involves drilling holes from the piston crown down behind the top ring groove, really helps the top ring seal.
Used a dingle berry hone to put the cross hatch back on the cylinders.
Had the cam reground, nothing real exotic, like 228 @ .050 .450 lift degreed in the cam to a 101 ICL.
Had the block and head hot tanked, which means I had new cam bearings put in. Also put in a new timing chain.
Put it all back together, and used a MSD ignition box with a MS3 Pro MPFI.
Used an oil pump off a Hydraulic lifer slant. Ran 15W 40 diesel engine oil in it.
Shifted that motor at 6500 rpm, ran great, not super fast was a 15 second car, the engine ran great, no oil smoke, never let me down. Also had long tube Hooker headers on it and the car was fully stripped out so it was not much more than a shell. Did bracket racing and I won races with that car-motor.
Built a new 275 hp slant and took that motor out, it’s in storage in the garage, it’s good for all that it is.
Personally for your build, I think the hot tank and getting the crud out of the inside and oil passages is money wisely spent. If your existing bearings are not scored, and are not far out of the top limit, re use them.
Same with the pistons - rings, do get the piston ring groves clean.
For new parts I would go with: cam bearings, valve seals, timing chain and a gasket set. Spend a little money on valve seats, raise the compression into the mid 9’s, and put a mild grind on the cam. And put the cross hatch back on the bores. Consider the hydraulic oil pump if the mains and rods are just beyond the high limit.
No guarantees for you, but this worked for me.