There are some good tips here
http://www.essexengines.com/tuning%20the%20essex%20v6%20page%201.htm especially the bit about avoiding high pressure oil pumps.
There is a lot that can be done with this engine, what you do will depend on if you want stock, mild or a fire breathing monster.
Also avoid boring to 60thou, I recall reading that it causes over heating problems because the walls are too thin. As I have just found, the alloy timing gears are noisy, but its slowly settling down. As I only have a mild cam (from Cam Shaft Shop New Zealand) I will probably put the nylon one back next time the engine is out.
Do it once, do it well :-)