Good evening all--hope everyone is doing well during these trying times.

To keep this post short: I'm trying to get my T-Maxx 2.5 running again. The backstory is that my dad gifted it to me back around 2003... We ran it together for years, always taking care to clean and lube all components after each use... around 2007 we stopped using it and it sat in the garage until 2015 when I brought it back out again for fun--the flywheel was badly stuck, but we got it loose, flushed the engine and carb with plenty of WD-40 and it was running fine... then it sat in the garage for a few years more.

The other week I used some of my newfound/forced pandemic time to try and get it running again. Applied plenty of WD-40 to the engine and carb, applied some new white lithium grease to servo gears, charged up the EZ-starter battery which I purchased new in 2015... but the engine won't start this time. The piston turns over without a glow plug in it, but when the glow plug is inserted it won't start.

I thought it might be old fuel stuck in the brittle fuel lines (fuel not making it to engine), or the glow plug. So I purchased new fuel lines and a filter, new glow plug, new glow plug lead (the old one was badly worn) and fresh air filter oil. The fuel I'm using was just opened this week, although I technically bought the bottle back in 2015... my dad and I figured it was still fresh enough for use since it was sealed all this time, but maybe we are wrong?

After all that cleaning and replacing and priming fuel into the carb, then clearing the engine in case maybe it was flooded, it still won't start up. Without a glow plug, it's turning and blowing out the WD-40 I've sprayed in, no problem. But as soon as I tighten up the glow plug up, it seizes. I recorded the video below to share here (shown starting with a fully charged EZ-starter battery, new glow plug, new fuel lines and new (old stock) fuel):

Any help or guidance will be very much appreciated! Thank you in advance.