What you are asking has no universal answer. Grounding kits (either commercial or DIY) have been made for several years with medium-to good-to great results depending on the application. Searching the Internet will give you dozens of ideas/implementations.
All of them fall in 3 categories:
1. "Star" configuration where all cables originate from a common position/plate on the battery ground and go out to the grounding points (most I have seen is 8 cables).
2. Daisy-chain where you do the obvious, start from a chassis or battery ground and connect all the grounding points in series.
3. Any combination of the above.
In all applications, results vary with the grounding points. Some work in a specific engine/chassis better than others. Even in two identical cars, if one has a rusted/dirty/cracked or whatever grounding cable/point that is not detected, different configurations give different results.
If you are going to try a DIY version yourelf and already have the parts/cables, I suggest you go all-out and try to ground everything in a daisy-chain fashion.
Points in series...
1. Battery
to
2. Chassis ground behind battery
to
3. Distributor
to
4. MAF
to
5. TB
to
6. Starter
to
7. Fuel rail
to
8. Intake manifold runner 3 or 4
to
9. Firewall
to
10. Intake runner 1
to
11. Right Strut tower brace
to
12. Chassis Grounding point under radiator overflow tank
to
13. right side of Valve cover or engine block
to
14. Alternator
to
15. Anywhere near the O2 sensor
to
16. Gear Box
I think I covered everything on the engine...
Chris
