I've done a lot of Ca conversions and the rules are something like this. First converting yours... there is no TBI conversion with a C.A.R.B. number so no go. Second you can put a complete engine from the year of the motorhome or newer and smog would be from the new motor... in this case you would be doing a motor transplant from a 1990 Chevy truck.

Having a good freind mechanic get you a sticker is usually the way to go to avoid little nit picking issues of making your 1984 BB a 1990 BB in the end.