Dont panic about the smog legality of the conversion, I spent about an
hour last Sat. getting a waiver on my stock 81 van and pumped the
referee about converting from the flat four and he stated ( in so many
words).If it is from the same year as your vehicle or newer and all the
parts are there and it passes the first inspection from a referee you
get a label that allows you to go to any smog station in Calif. and get
inspected .  I would go ahead and swap just make sure its from a smog
legal car and every nut and bolt is stock, if you change the smog device
or leave off parts you must spend as much money as neccessary to get it
legal, no cost waiver for you!
        Hope this helps
        DrRufo
        SOCal 81 vanagon