240z strut tower?

So, I am doing my struts on my 240z. and noticed different part numbers on the strut towers of the two different cars I have here.

Was there a different strut tower used in the 240z line? I know the ball joints are different on the early cars.

Is there a reference of what the part numbers are for the strut towers?

I have two different numbers for the passenger side

54302-E4151

54302-E4150,

Is it just a superseded number?
Thanks
Bob