Info needed: 1967 M38A1 Lubrication?

[Les Kovacs]

I am now confused about which spark plugs to use....I finally pulled the plugs from my M38A1-CDN2...the first plug closest to the rad was an Autolite 2245...the rest of them were Autolite 2243.....all 4 came out well and all 4 had a light tan colored resistor/ceramic (is this good?).

OK...so which spark plug (Autolite 2243 or 2245)is correct for this application (F head) as I am confused. An on line jeep store sent me Autolite 2243's a month ago before I realized that there may be other more appropriate applications.

Thanks for your response.

les