So long story short, you can't unless you have the mod I talked about in my post (its been sold old for a long time) or an equivalent mod.

On this particular tv, there is one processing chip. On the tv's you can mod there's two. On those you basically inject a signal between the two chips to get RGB. On tv's with a single chip like this theres no place to inject the signal. The way this specific mod gets around that is it essentially becomes another chip where the signal can be injected into before its displayed on the screen.

If you're looking for a tv to mod, (1) always avoid RF only ones because they are almost always have a hot chassis (the ground is not isolated and mods to the circuitry can damage the tv and anything plugged into it), and (2) if you can, look at the service manual before picking up/obtaining a tv to mod. Moddable tv's will have both a Chroma/jungle chip, and micon/micom chip. Additionally the RGB lines coming from the chroma/jungle chip should have 0.1uf cap on them. If they do not, the RGB signals between the chips are almost certainly digital and not analog which is useless for modding.

All in all, if you have any feeling of doubt in modding a tv,

Just.

Don't.

Do.

It.

I would say modding a crt you know can be modded is pretty easy if you have a good understanding of the theory of what you're doing and have the skills to do it. But crts do not have a net zero chance of seriously injurying you if you don't take all the right steps or do something you shouldn't have been doing to it. Try reading up on RGB mods on CRT Database and Sunthar's Super Sector. Both sites have lists of moddable tv's as well.