OK, so ME(D)9, I can see how maps are referenced and also how ram is accessed, that is fairly simple.  What I can't see is how, for example rl_w, is set in ram from it's parent function, there's no code like mov rl_w r4; (like C167).

I'm assuming it's using a stack and I need to read more but any prod in the right direction would be helpful.

+1 for you my friend, thank you, it was staring me right in the face

Look for powerpc.

I usually look into damos/a2l file.
For example i took a binary and a2l file from here
http://nefariousmotorsports.com/forum/index.php?topic=467.msg74873#msg74873
(These files came with WinOls in damos folder).
In the file clearly see memory structure, all segments & addresses.
Also if you scroll down the file you will find proper addresses of all variables for the bin.
So I think a2l file is very useful as reference for disassembling.
For example, here is clear description of segment structure, you can make same segments in IDA:
    ECU "MED91"
    /begin MEMORY_SEGMENT Pst20000 "" CODE EPROM EXTERN 0x20000 0x1A0000 -1 -1 -1 -1 -1
    /begin IF_DATA ETK ADDRESS_MAPPING /*orig_adr:*/0x20000 /*mapping_adr:*/0x20000 /*length:*/0x1A0000 /end IF_DATA
    /begin IF_DATA ASAP1B_CCP ADDRESS_MAPPING /*orig_adr:*/0x20000 /*mapping_adr:*/0x20000 /*length:*/0x1A0000 /end IF_DATA
    /begin IF_DATA ASAP1B_KWP2000 ADDRESS_MAPPING /*orig_adr:*/0x20000 /*mapping_adr:*/0x20000 /*length:*/0x1A0000 /end IF_DATA
    /end MEMORY_SEGMENT

    /begin MEMORY_SEGMENT Pst1F0000 "" CODE EPROM EXTERN 0x1F0000 0x10000 -1 -1 -1 -1 -1
    /begin IF_DATA ETK ADDRESS_MAPPING /*orig_adr:*/0x1F0000 /*mapping_adr:*/0x1F0000 /*length:*/0x10000 /end IF_DATA
    /begin IF_DATA ASAP1B_CCP ADDRESS_MAPPING /*orig_adr:*/0x1F0000 /*mapping_adr:*/0x1F0000 /*length:*/0x10000 /end IF_DATA
    /begin IF_DATA ASAP1B_KWP2000 ADDRESS_MAPPING /*orig_adr:*/0x1F0000 /*mapping_adr:*/0x1F0000 /*length:*/0x10000 /end IF_DATA
    /end MEMORY_SEGMENT

    /begin MEMORY_SEGMENT Pst0 "" CODE EPROM EXTERN 0x0 0x20000 -1 -1 -1 -1 -1
    /begin IF_DATA ETK ADDRESS_MAPPING /*orig_adr:*/0x0 /*mapping_adr:*/0x0 /*length:*/0x20000 /end IF_DATA
    /begin IF_DATA ASAP1B_CCP ADDRESS_MAPPING /*orig_adr:*/0x0 /*mapping_adr:*/0x0 /*length:*/0x20000 /end IF_DATA
    /begin IF_DATA ASAP1B_KWP2000 ADDRESS_MAPPING /*orig_adr:*/0x0 /*mapping_adr:*/0x0 /*length:*/0x20000 /end IF_DATA
    /end MEMORY_SEGMENT

    /begin MEMORY_SEGMENT Dst1C2000 "" DATA EPROM EXTERN 0x1C2000 0x2E000 -1 -1 -1 -1 -1
    /begin IF_DATA ETK ADDRESS_MAPPING /*orig_adr:*/0x1C2000 /*mapping_adr:*/0x902000 /*length:*/0x2E000 /end IF_DATA
    /begin IF_DATA ASAP1B_CCP ADDRESS_MAPPING /*orig_adr:*/0x1C2000 /*mapping_adr:*/0x5C2000 /*length:*/0x2E000 /end IF_DATA
    /begin IF_DATA ASAP1B_KWP2000 ADDRESS_MAPPING /*orig_adr:*/0x1C2000 /*mapping_adr:*/0x5C2000 /*length:*/0x2E000 /end IF_DATA
    /end MEMORY_SEGMENT

    /begin MEMORY_SEGMENT ExtRam900000 "" VARIABLES RAM EXTERN 0x900000 0x2000 -1 -1 -1 -1 -1
        /* AsapMLXFm - CCP_V2_1 */
    /begin IF_DATA ETK ADDRESS_MAPPING /*orig_adr:*/0x900000 /*mapping_adr:*/0x900000 /*length:*/0x2000 /end IF_DATA
        /* AsapMLXFm - KWP2000 */
    /end MEMORY_SEGMENT

    /begin MEMORY_SEGMENT Ram7F8000 "" VARIABLES RAM INTERN 0x7F8000 0x8000 -1 -1 -1 -1 -1
    /end MEMORY_SEGMENT

    /begin MEMORY_SEGMENT Ram800000 "" VARIABLES RAM INTERN 0x800000 0x8000 -1 -1 -1 -1 -1
    /end MEMORY_SEGMENT

OK all is clear about RAM ROM settings but how can I find correct TOC and SDA settings ?

Nice work, remember the SDA/TOC are platform independant

i did not see that you were talking about edc16c35 in the previous posts...Never tried to disassemble this one.But when you cross reference the sections you are interested in with a damos i am sure you will be able to find the correct toc/sda addresses.