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I have my share of EPROM programmers that program 2716 EPROMs, and I have my share of 2716 EPROMs as well. I use these in most of my 8048 projects. Now, I do also have some 8749 chips that I got at auction. With my focus on the Odyssey2, though, I'm not doing much with them now. It would be cool to plop an 8749 into an Odyssey2 some day. Anyway, I came up with a good idea to program my 8749 chips, but I don't want to take the time to build the circuit right now. The parts you need are: 74ls244, 2716, (3) 74ls193, (3) transistor amplifier/switch circuits, and a crystal. Put the data output of the 2716 on the bus of the 8749 (or 8748, for that matter). Cascade the 74ls193 chips so that they count up to 2K. Put the 74ls244 between the lower 8 bits of the address, and run that to the bus of the 8749. Run all addresses to the 2716, and the upper 3 to the 8749 (p20-p22). Use a PC parallel port to reset the counter and count up. You can then use the remaining lines on the PC parallel port, combined with the transistor amplifier/switch circuits to program the 8749. Enable the 74ls244 and 2716 at the appropriate times. You might find this article helpful if you want a circuit to isolate your PC from the programming circuitry. There is a fabulous plan for building your own standalone programmer as well, here. When you unzip the programmer files from this site, note that you can just run these directly in to a PCL-compatible printer. For my HP laser printer and GNU/Linux box, this means I just go lpr -l blah.fil, and it sends the file out to my printer in raw mode. There are circuit board layouts, schematics, everything you want. Stay tuned in to Coprolite, and I'll build up the 2716->8749 programmer and document it some day.
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