I'll give you a quick example with the 3530A firmware 3.01 - maybe you can try to figure the rest yourself
The mediacodes for DVD-R start at offset 0x20cfc. The first Byte of this mediacode starts with an index that's used for grouping mediacodes which share the same strategies. Each entry takes 16 (0x10) Bytes.
Then at offset 0x2242c you have a table for the media groups with 4 Bytes for each entry. The first two bytes are the index to the actual writing strategy for the first speed, the next two Bytes indicate the supported write speeds. Each write speed has a bit that needs to be cleared. There are also strategies for write speeds that you cannot select but which are used when the drive increases the write speed. The speeds that I found are 1.0, 2.0, 2.4, 4.0, 6.0, 8.0, 10.0, 12.0, 14.0, 16.0, 18.0, 20.0, 22.0 and 24.0 - one or two bits are unused yet even in firmwares for the latest drives - even more bits in the 3530A as it doesn't support >16x speed.
The actual strategies start at offset 0x16f2c with a length of 76 (0x4c) bytes each.
Then there's also the total number of media groups at offset 0x226d0 and the total number of strategies at offset 0x226d2 but if you want to change this data (increase the value), you'll also have to move the tables to a free location and adapt the assembler code that retrieves the data.
The strategy sizes differ between different mediatypes and (sometimes but not always) between different drives. NEC also once changed the structures between two firmwares for the same drive in order to save space.
These are all the offsets that I found for the 3530A firmware 3.01:
Good luck and one last hint: The firmware start searching for the correct media ID with the last entry getting back to the first one which is (as far as I remember) then taken if nothing suitable is found.