[Frank Lee]

All the changes individually probably got fractional hp savings.

Many figures online (hard to find good ones at all) only show peak loads- 6000+ rpm. Super Chevy did a water pump dyno test and didn't even report results from below 3000, because they couldn't measure it.

So by slowing water pump down I might have gained .1-.3 hp?
Alternator @ -45% speed... more efficient and less cooling fan losses... <1 hp?
Power steering- some reports showing 5 hp @ peak rpm, others about 9 hp... similar to water pump, so at 2000rpm and less, probably <1hp.
More efficient belt routing: no idler, no tensioner, no backbending, shorter belt... <1 hp.

Probably reduced load by at least 1HP but less than 2 or 3... sounds fruitless right? But if the car is only using 12hp to cruise, power accessories could be taking 10-25% of the power.