I'm pretty sure only the p610 crossmember will fit the b210, and even then it will sit the engine too high. A10 (stanza?) crossmember IIRC is used for L-series into b310 swaps.

B210 and 1200 (B110) are nearly identical, so the L-series swap for 1200 instructions will apply to the B210. The main advantage is that B210 can use the A10 (new 510) or 710 (180B) crossmember so it is more of a bolt-in.

With the 32/36, you don't need dual carbs. The 32/36 flows enough for all the HP an A14 can make. My advice is fit dual-springs on the valves, and get a cam for max 6800 RPM. It should be a noticeable increase in power.

But fitting a stock L20B will give you even more power, for less money than your modified A14.

If you go for a bigger cam you might want to think about multiple carbs to get the most out of it.

As for the L series upgrade it should be pretty simple as they were an option from the factory. I know you use the crossmember from a 180B.

I got a B210 with a A14. It has a 32/36 webber and racing header. I've noticed an increase in power, but now I'm considering a new cam. How much more of an increase am I looking at with a cam upgrade.
I've also considered swapping to a L-series for more power but the info is very limited. People have done it. It's just that there isn't a step by step like with the 1200, 510, and 1600.
Just looking for some advice.
Thanks