Heresy? Ford 3.8L v6 swap > ‘87 Nissan Z car

We're looking to utilize the 1999 - 2003 3,8L V6 in our race car but our 3.8L must remain "stock". Consequently stroker kits, nitrous, wilder cams, etc. won't meet our sanctioning body restrictions. Nor will dry sump. What we're looking for is tweaks that can be made to the stock 3.8L motor to improve reliability for endurance racing and very basic engine modifications that will add some HP over the stock 190hp. Examples:

PERFORMANCE
1.) ECU tune - how to or who does the best one
2.) X pipe or H pipe dual exhaust and what stock headers flow best (deliver the most HP)
3.) Stock dual runner intake tweaks that might improve intake flow/performance (throttle body and MAF must remain stock)
4.) CAI DIY solutions - the engine will be in a Nissan 300ZX so general placement ideas and DIY materials
5.) Does this engine respond well to retarding the cam and if so, by how much
if we can get 10-20 hp with these changes we'd be quite happy

RELIABILITY
1.) stock oil pan baffling or DIY solutions for better oil flow, control, and cooling. Our car generates about 1G in high speed corners so keeping oil around the pickup is crucial. Our recent Nissan engine failures have been due to oil starvation
2.) what's the "best" oil pump, water pump
3.) "best" stock replacement pushrods, valve springs, rocker assemblies, roller rockers
4.) stock or aftermarket remote oil filter and oil cooler solutions
5.) common failure points and solutions

Ideally we like to see actual dyno results or instrumentation that demonstrates effectiveness