Be aware that there are some quite significant differences between the LST(1) and LST2 or XXXL. The LST2 is much stronger and more durable than it's predecessor, getting an LST to LST2 spec isn't going to be cheap.
I think the chassis rails are beefier, the A-Arms, rear fixed hubs, c-hubs, steering knuckles, CVD's are all stronger than those on the LST.
Find out if it's have any of those upgrades to see if it's a worthwhile trade.