Engine starting to knock/tick.

[DarkSupra2.5]

I'm pretty sure my engine is about to die. I just got through replacing the release hub for the clutch, fun job btw with no tranny jack. But I was all happy and about to go drive and get gas when I start her up and she knocks around like there's a hammer in the block almost.

I figure, crap, I'm royally F'ked. But, it goes away and leaves behind an even nicer ticking sound that get's louder if I rev it. Needless to say, I haven't run it since. I'm going to pull the lower end apart this upcoming week as long as the weather holds up. But now here's the question.

Since I have a 1jz, would I be better off rebuilding it, or going and getting a 2jz block from a MKIV or SC300. There's two SC's in PNP near my place, so I figure I'll do a hybrid jz engine. But I'm just worried because the ticking isn't loud, and sounds like a valve, but it sounds to low in the block to be a valve. I've searched and found other guys with the same problem, only for them to just replace the engine anyway and not deal with it. But I can't do that. So, hence I'm hoping for other mindsets for input on what the sound might be. Friend of mine said I might have pushed one of the dowels in the flywheel back into the block side of the flywheel causing the tick, so I'm going to check that to. But any other suggestions would be appreciated.

I'd hate to have to get rid of my jz, but I just might have to at this point if the crank is screwed up if I happened to spin a bearing.