99 obs tahoe 5.7 to 5.3 conversion opinion

i want some opinions on what i should do, i have a 99 tahoe with the 5.7 with 180.xxx miles in it, had a bad knock that got worse so i parked it, in the process of pulling the motor and rebuilding it, well i found a 5.3 that my friend is not using, has wiring harness, pcm and everything, full motor, havent got the full details on the motor yet like the mileage or year it came out of. would i be better off rebuilding the 5.7 which im not sure how much will cost or putting the 5.3 in it which i can trade some stuff and basically get it for free and if so, what all would i have to change to put the 5.3 in and is it worth the trouble, thanks in advance

if it were me and I had to keep the tahoe then the 5.3 would be going in. 5.7 will be pricey to rebuild and still have less power and fuel mileage after the rebuild.

I don't know about the mileage being better. My 99 2-door Tahoe I had with the 5.7 got better than our 2003 does now. Hard to say...
Really depends on if you want a drop back in engine or something you may have a couple of headaches before you get it running.

I know it wasn't one of the choices , but a 6.0 would be perfect in it !!

^^ basically the same thing with bigger pistons.

as for the swap - check out the LS conversion threads

thanks for the input, looking at dropping the 5.3 in it or selling it as of right now