TRS-80 Question

[Bill Gunshannon via cctalk]

Here's one for whatever TRS-80 gurus still hang out.

The Mode 4 had 64K RAM and pretended to be a Model III by loading
an image of the Model III Rom and then running it.  Would it be at
all possible to do the same thing with an image from the Model I
and thus make a Model 4 capable of running Model I programs?

bill