1952 A10 spark plug question

[chaz]

the A10 could do with a pair of plugs, Ive run out on the shelf but getting confusing results..
1952 650 Iron head engine running monobloc 376 carb

Ive seen B7ES on ebay, B6HS on Drags and NGK web/catalogue, the parts book says either 65-114 or 67-529 (cant find a NGK or Champion equiv). the N4c I have for the B40 and A65 are longer reach than the B6HS currently fitted .
any reccomendations?

[idie]

L10 or L86 Champion.

[Bess]

Hi Chaz,
            I have this  info, the long reach is for the alloy head:

Best wishes...

[chaz]

thanks idie and Bess
the N4C is too long, the B6HS is what was in there so its the same or an L82C as Champion have compacted their range unlike NGK which get bigger