system100m diy?

[Doctor Schinkelfunk]

Hi,
I am new to the list, and new to synth-building. Fed up with my not so 
analogue sounding syths as the jx8p and the obmx, I decided I wanted to 
build my own.
I started with building the filter and tb3030 from Tony Allgood. Very nice, 
that's more like it!
Now I got hold of the service manual for the Roland system100m, and I was 
thinking of building it. 

Does anyone have any suggestions about it, or tips, or maybe alternatives? 
One problem are some parts. For instance the BA662 A and B are used a lot. 
Tony subsribes a BA6110 from Rohm. Is it a good replacement for the 662, 
also in the filter?

Thanks a lot,


Corneel.