Hi Grant,
No problem. I attach the adapter schematic as PDF.
However I can only recommend to also install the soft, very intuitive to use, and you can use it to make extensions.
For programming I've used various assemblers (TASM).
But over time it find it too tedious to do anything more complex.
ELEKTOR has issued good series of introduction into 8051 systems.
There I made experience with AT89C8252/53.
Cool guys, ISP, with RAM, FLASH and EEPROM on board.
The right Connector for ISP-Programming could also be added to the adapter.
Otherwise there's also a cute PASCAL compiler (NILIPAS) for easy programming.
And for more serious stuff, Keil C compiler cool stuff, professional and widely usable.
Cheers,
Haitar