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You can try for fun, but you'll have VATS issues if you don't have someone flash it. 98-00 all used the later computer. 2wd and 4wd matters as does factory tire size and gears between the 2.
Pretty sure I mentioned this in your other thread... But like others have said you're going to need a tune unless the PCM you swap in came from a pretty much identical truck. Even with a tune, if your truck is pre-'98 you're still going to need a PCM from a pre-'98 truck because of the PassLock issues. Even though yours is a '98 and the Tahoe is a '99, you'll probably still need a tune to overcome the anti-theft problems.
That's why I suggested buying a performance tune from someone like Black Bear Performance and paying the core charge for a spare PCM from them. Your only other options that I can think of would be to swap in a PCM from an identical truck (engine, trans, gearing, year, etc.) and pray it works, or buy a used one and have a dealer flash a stock tune for your truck to it based on the VIN. Never done the latter, but I'd imagine the amount of money involved would be similar to buying a performance tune. At that point, I'd just buy a tune from Black Bear and enjoy the additional benefits.