You have a big problem. You need to get some kind of code in there to bootstrap your real code into RAM. And to get the code there ????

What you REALLY need to do is try a Dallas DS5000, which is a pin-for pin replacement for an 8031 which can be loaded through its own serial port.

Or an Atmel AT89S53, with Peter Danneggers neat little programmer to load it.

You COULD if you had almost infinite patience and a lot of switches load the boot code into RAM manually, but one small error and you could need to hit reset....

Steve