Yes, the TMS4100 and TM4103 have the same pinouts (I worked from the 'wrong' data sheet when I produced schematics for this machine, they're available from the Australian Site (one page missing?) or on the HPCC CD-ROM).
The boards in the 9830 are :
At the very back, the I/O backplane with the 9866 interface circuit (a simple-ish parallel port) on it.
09830-66551 PSU
11275-66584 expansion RAM (loads of 1103 DRAMs)
09830-66584 standard RAM (ditto, they're actually much the same PCB)
09830-66583 Memory Data (T register, etc)
09830-66582 Memory Address (M register, address decoder)
(Can't remember, but full width in front of those) : Main ROM
09810-66514 CPU Data Path (registers, ALU, etc)
09810-66513 CPU Control (Microcode ROMs, etc)
09810-66512 CPU Clock (and I/O state machine)
09810-66511 CPU I/O Interface (I/O register)
09830-66525 Extension ROM selector (address decoder)
09830-66526 Extra ROM (that wouldn't physically fit on the main ROM board!)
In front of that are 3 slots for internal ROM options, like your plotter ROM.
09830-66561 Tape Interface (and beeper, etc, that's the one with the speaker on it)
09865-66562 Tape Controller (shift register, etc)
09865-66563 Read/Write (for the tape drive)
09865-66564 Motor Contol
09830-66542 Display Driver (that's where this character generator ROM is)
09830-66541 Display
The keyboard is a total of 4 PCBs, all with 09830-6653x numbers. The keyboard itself, the encoder board that screws to the bottom of it, the interconnect board that plugs into those 2, and the paddleboard wired to it that links to the main backplane.