Honda BF 9.9 Running rough, replaced carb - now wont ignite

Aloha!
I have a 2007 honda 9.9 was running a tiny bit rough when i first got it, a little intermittent backfiring at WOT. Condition steadily decreased and last time i took it out it was really unstable I am not sure if it was backfiring or hesitation or missing but it was running quite rough. Ended up dying on me on the water and would not restart. After about 2 hours I was able to get her goin again and limped into the docks.
My plan was to clean the carb up but it was so seized up i busted it up tryin to get it apart so I ordered a new one. Just put it on tonight and been trying to start it for an hour but she wont light up. I have spark at both plugs, new fuel filter, fuel hand pump is tight, If i open drain plug fuel comes out of bowl.
I sprayed starter fluid into the carb and still no fire up.
The guy i bought this boat from did not take care of his stuff very well the oil was black as night and he had a quart of 2stroke oil in the boat (its a honda 4stroke) not sure what he was doing with that but whatever.
Any thoughts?
Thank you for your time!

Pulling the rope for an hr ??------Backfiring ?------Check valve clearance.------Check compression.-----Check belt timing.-----Test for strong spark.

If it won't fire on starting fluid it's probably not a fuel delivery issue. I agree with racerone...all the checks he suggested would be the next steps. I would:

1. Verify cam timing

2. Check and adjust valve lash.

3. Perform a compression test.

Done in that order will yield the most reliable information about where this engine is at and what work might be needed.

You should have a shop manual if you're going to do the job yourself.

Good luck