Stucco to replace T111

I bought a 1950s repo last December and have been mainly focused on the interior up until now. I finally have enough done inside that I can start thinking about the exterior. The previous owner enclosed the carport and used T111 wood siding. The rest of the house is stucco. The carport enclosure addition was done without a permit, so it goes without saying that the quality of work done could be better. The majority of the T111 needs to be replaced. It was not sealed well, and there is no flashing or protection along the bottom edges. When it rains the siding absorbs some moisture through the bottom. Fortunately I live in Southern California and it only rains a few times a year.
I would like to make the exterior look more cohesive and stucco the carport addition. I don't know if it is possible to stucco over the T111, or if that is even a good idea. I am not really concerned about water damage behind the siding, we did a lot of gutting on the interior and there were no signs that water had damaged anything other than the exterior siding.
Also, when the previous owner poured some concrete around the exterior of this addition, they poured it directly against the siding. I am planning to rip out that concrete and redo it (its cracking and uneven). I am sure that when I do that some of the siding is going to come off with the concrete!
I'd like to know the most cost effective way of redoing the exterior of this portion of the house. If it is going to be significantly more expensive to replace the siding with stucco, I don't know if I would do it. Although I know that the aesthetic value of having the exterior all one material may be worth the extra cost.
Any suggestions?

It is doable, but do not expect great results in the future when the T-111 moves because it is probably 2 feet on center attached to the framework. Then of course it could also be fine since you do not get alot of moisture where you live, so the movement may be minimal.

Just repair or replace any of the damaged T-111. You also want to paint all the edges if the plywood is painted already o keep it consistant.
Then fasten it all down with some ringshank nails that will not pull out.

Then have a licenced contractor come out and give you some $$ amounts to install. Get more than one, and do your homework on types of stucco in your area. Good luck.

I would remove the abutting concrete, dig and pour a new foundation, footing and short wall to get the bearing needed for the new stucco. To build a stuccoed wall on a carport slab without perimeter footings to support it would be foolish. Then your H.O.Insurance would cover it when the "Big one" shakes. You'll have it permitted and paper trailed.

Be safe, Gary