The best advice would be to talk with the folks who will be inspecting / approving the vehicle after the engine swap.

As a general rule, when an engine is swapped the engine must be newer than the vehicle into which it is swapped. The older vehicle must then meet the emission standards of the donor vehicle.

I've read that some picky inspectors will make a big deal out of the type of gas cap that is used. Newer vehicles have gas caps which thread into the filler neck and then click when tight. I've read on a GM forum that some guys vehicles have been rejected because their vehicle still had the older 1/2 turn type cap on it. 1

To do a conversion right is a hassle, but a newer engine would have some advantages.