You installed the tps wrong. Remove it and make sure throttle is at idle. There is a small coupling in there. Don't lose it. After you re-install the tps, move the throttle cam by hand and feel for any binding or hard stop. Watch the throttle plates. If there is, you may have yet installed it wrong. 180º wrong.
Since you can destroy and engine over-revving it with no load, why not make the next test start in the water. You don't even have to take it off the trailer. Leave the stern tied down.