89 PRO-V 150 jetting

[<rbmopar>]

I recently bought a Hydrostream with an 89 PRO-V 150 on it. I was told it has a phase II Yamaha performance kit on it. The thing runs pig rich through the rpm band and basically dosn't idle. The jets in it are 168's. At the price of jets I am looking for some advice before I buy some.I am new to tinkering with outboards, though I figure it can't be much different than jetting a snowmobile. Any info would be greatly appreciated.

[<rbmopar>]

I forgot to mention that the previous owner cut slots in the exhaust section of the lower unit to reduce backpressure, I presume. The slots are 1/4"X3". I would like to weld these up because it's awfully loud with the family in the boat. Thought this might change the jetting also?

[<boats.net>]

I am not sure what you have there the original jets are 124, but dont know what has been modified on engine