Disassembled the A15 block and it looks in real good shape. I can still see the original cross hatches. Engine has about 130k mlies. Will get Plastigage to check bearings and will also check end play. And will also check cylinder bore. If I don't require machining I may want to try and clean the block itself without hot tanking. It was suggested not to do this so that I can preserve the camshaft bearings. Any ideas or methods on doing this? Coolant passages requires serious cleaning.

Yes, many A-series engines don't need rebuilding, nor even a ring replacement -- good for about 200,000 miles. The first thing to wear is the valve guides, so replacing or knurling those is often all that's needed.

To clean the coolant passages, do a "coolant flush". Run a hose through the block, with or without a chemical flush product.