Has anyone tried to put a L20B engine in a 210 US model
car?Will it fit?

The L series engine was an option in Japan for the B110 & 210 .The 310 Sunny shares the same chassis dimensions as the Silvias and by using a Silvia crossmember an L series or FJ 20 will
drop in. As has been said before look for a Auto trans model for the bigger tunnel in the B110 & 210 model range and the job is far easier. I used a cut and shut L series cross member to
repower one of my 1200s. Weld some scrap angle iron across the L series mounts and cut them off the X member, then cut the A series off it's X member then weld the L series mounts onto the A
series X member. Just tack weld it first then dummy up the engine to see if everything clears, sump etc. At this stage you can lower the height of the mounts to get the engine lower or
further back. If done neatly the job can look factory and most people will never appreciate your work.