Mercruiser calls for the AC CR44N, or NGK BR6ES.
The BPR6ES is basically the same as a BR6ES as far as how it works. The only thing different is the overall plug height and a fixed or removable terminal end on the plug.
And Don - cheers buddy - thats the conclusion i came too as well - nice to hear a guru confirm it though.
I can see how you got it slightly wrong fishermark - the GM I/L4 120 took a different plug up to SN3825578 - then 3825579 on is as you say the BR6FS - it was the P bit and the length i was double checking - but hey mate as I say very grateful for the input
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