Engine blow up - so will any ST1100 engine fit any bike?

So, after 4 years off the road (another story), I spent the last 6 months restoring my '95 ex police ST1100. Total respray, new oem silencers, Corbin seat, powder coated wheels, the full monty. I even made a really nice analogue clock using and old voltmeter casing to match the police voltmeter on the bike.
Unfortunately though... 20 miles down the road on its first trip out, sudden loss of power, BANG and a ton of white smoke from the exhausts. I'm guessing the cause might be the timing belt in one position for 4 years, but not sure. What is sure is the engine's a dead'un. That's the bad news.
The good news is that you can pick up a second hand engine on ebay for ?250. So... my question is, will any ST1100 engine fit any ST1100 bike? Mines a non-ABS bike.
I'd welcome an expert opinion.
Many thanks
James

I think the only difference would be the '96 and newer... no need for the oil cooler because the alternator is air cooled. The mounts should be the same. Have never done that before, so I can't say for sure. There could be some minor wiring harness differences but not sure about that either.

One would need to know the year of the donation engine to determine for sure.
Besides the change for the air cooled alt (oil cooler eliminated) the water-pump was altered as well...
Some early years had a different case-vent (located on the aft end instead the forward base of #1
And then there is the question of PAIR system, as some years/engines did come without it (blind cast flanges on the heads where the chromed pipes of a PAIR system would connect)

James. This is not the end of the world for the engine. You are right though, it sounds like a timimg belt failure - they do not like being in the same position for to long. I know of another ex police pan that this happened to (ex Strathclyde bike). The owner sold it on as he thought the engine was toast. New belt and a couple of small parts and the new owner had it back up and running. Not sure of what parts as it was a few years ago. Might be worth looking at rather than going straight for the replacement engine.

Your diagnosis is probably correct, but I've heard of other engines that have seized for another reason, and so did mine. It was the alternator case that had cracked open with corrosion and jammed the engine.

However, as yours started and ran for a few miles, I think you would've heard a loud whining from the alternator as it was seizing. Oh, and alternators are usually more expensive to buy than a used engine in the UK.