Programming ATmega fuses with a stand-alone programmer

I have successfully followed Mr. Nick Gammon's very clear tutorial (http://www.gammon.com.au/forum/?id=11637) to burn a boot loader and then upload programs onto a stand-alone ATmega 328P running "Atmega_Board_Programmer".

Unfortunately, I could only burn the boot loader by placing an external oscillator. It seems that as a result of this the Low Byte fuse got set to require the external oscillator both for loading programs and running them. I know I need to set the Low Byte to 0x62 (or preferably 0xE2 since I do not want to divide the clock by 8).

Mr. Gammon has a "board uploader" sketch that he says can allow resetting individual fuses; this is exactly what I am looking for. But it seems that it only works for uploading from an SD card. I cannot get it to work from the arduino IDE.

Is there some file that I can edit (and where are these hidden on the Mac), perhaps one called by Atmega_Board_Programmer or by Atmega_Hex_Uploader?

I have seen examples of AVRDUDE command lines, which I would think could solve the problem just as well, but I am running on a Mac and have very little familiarity with such operations. Would I just open terminal and type in the command line, that's all? Seems too simple. And if so, what would be the ISP I am to put in the command line? I am writing the programs using the Arduino IDE and loading them to the stand-alone chip over an FTDI basic.

I thank my readers in advance.

You cannot change the fuses without either an external programmer (like a USBAsp - they're $3 shipped on ebay and "just work") or another Arduino running Arduino as ISP sketch (included with IDE).

There is more to running off the internal oscillator than just setting the fuses - do you have a board definition installed that specifies 8mhz speed instead of 16? You need that.

I would suggest you install minicore by hansibul/MCUDude https://github.com/MCUdude/MiniCore and then it's as simple as wiring up the programmer, selecting board and clock from tools menu, and doing burn bootloader.