My following content is based on your comment that you are a carb virgin. If you were a carb guy, I would tell you to pull em off and go thru em. But you're not. As far as what they are, they are QJets. You do need a torx set, although you can "make" a regular set of hex keys work in a pinch. The carbs are pretty normal and a car rebuild kit will work fine for all parts except one. The needle seat. The ones in your carb are stainless steel HIGH FLOW ones. The ones in all the kits are normal flow. The kit float needles will fit either style of seat, so you can use the loat needle, but KEEP your existing seat. Take it out an clean it if you need to, and use the new gasket when you reinstall it, but don't use the automotive seat. But since you are a carb virgin, the following is my advice to you.

If the boat runs as well as you say, then leave them on the boat.
Your idle mix screws stick out from the base plate on each side at the front. If it's idling smoothly, then leave em alone. Set the idle STOP screw to get them to both idle at about 700-750 in gear with the cables disconnected.

Clean the arrestor with solvent/degreaser/carb cleaner and compressed air from the inside out.

Adjust the throttle cables to be sure you are getting the throttles fully closed at idle and fully open at the other end of the throw. Then play with the fine adjustment a bit to get the levers fairly close at your favorite cruise speed, but always recheck after to see that you are closing all the way and opening all the way. Mine levers run a detent or two off, No biggie. You should expect to tweak at cruise to sync the motors by ear anyhow.

Tachs. Dont' trust them. Run at fast cruise (4000) and sync the motors by ear. When you get them sync'ed, check your tachs. They may or may not be reading the same, but the motors will be within 20 revs of each other if you got them synced good.

At WOT, 70rpm difference can be anything from tach error to a bad plug wire. You get about 40hp per slug, and a dead cylinder usually won't hurt you more than 100 revs. You should be abl to feel it in your feet thru the stringers though.

hope this helps

Very cool guys. I can't thank you enough for breaking it down for me, specially the little stuff like the stainless seats. That's the kind of stuff that would get me in trouble, and if I didn't know before hand a carb rebuilder might not know? They're gonna stay bolted on until the motors come out.

I'm going to go through the flame arrestors, check the cables, then I "might" mess with the idle. I need a meter or whatever to compare the tachs to right off the motor.

mcollinstn, I wish I had developed that sensitivity by now And with my Silent Thunder platform you can barely hear the motors while underway. Most of the Formula guys drill a bunch of holes inside the platform; doesn't improve performance but at least you get more sound
I can't thank ya'll enough,
Michael

Silent Thunder is plenty loud enough to synchronize by ear. Heck, thru the outdrive exhaust is loud enough to sync by ear. Its the harmonics that you listen for. Start with one intentionally slower than the other at a 3500 rpm cruise. Maybe 500 revs slower. Begin bringing the slow motor up a little at a time stopping for 10 seconds at each point. As the motors get closer to the same speed, you will hear the harmonics cycling quickly "wawawawawawa", and as you get them closer the cycles will start getting farther apart "waaawaaawaaawaaawaaawaaa" and closer will bring the cycles farther still "waaaa, waaaa, waaaa, waaaa".
Until you are on top of "sync'ed" with a single very long "waaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa". If you go too far the other side, the cycles speed back up again.

You know you got it right, when you have one long waaaaaaaaaa, and it starts cycling when you turn a bit to port, settles into a single cycle when you straighten out, and starts cycling when you turn a bit to starboard.

Play with it. It is SO much easier than it sounds.

I've had to do it for years on old twin houseboats with thru prop exhausts. Can't hear em for crap, but you can "sense" the harmonics below the background noise.

I wonder if this technique works in bed with twins?