Prop wise it's hard to say. Some boats run better with two blades and some run better with 3 blades. The 3 blade your running has a little to much slip witch is why I said send to la prop. La prop has a technique he uses and you will see some small gains.
Exhaust wise all the major brands you will see gains some more than others. From the dyno charts I have seen from the 37's it's been 2-4 hp gains witch isn't much but every little thing makes a difference

2 - 4 hp on a 37 hp motor is fairly significant in my eyes. Which ones were you seeing that on?

You could gut your stock exhaust and save a dollar or $400.

I want to keep my stock exhaust, in case I ever wanted to go back for noise or whatever reason. Probably won't be shelling out the cash for exhaust just yet but I was just curious since it sounds like he saw some number from a dyno test.

Voodoo is the best performing exhaust then next would be stainless works

That's pretty cool. Good to know. So for reference you'd be paying about $200 per hp maybe a little less...

The uflex system is working excellent. The notch is not necessary, what you need is the reverse mount. The standard mount is either port or starboard and you need the other. I'll get the correct one and post it later. I highly recommend this system, the uflex guys helped me figure out the correct arm and were super helpful. Nothing sticks out to get caught on and it's got plenty of hydraulic power for cranking these motors back and forth.

Ok just ran down and checked. You need the port side.

Ok thanks Buddy!

BTW great looking boat!!

Thanks!