Plug question, '71 evinrude 25hp

Got around to tuning up my new to me 71 Evinrude 25hp, The plugs I pulled out of the motor were Champion J4J and probably 20-25yrs old although not in horrible shape. Just as a check I looked up the motor in the Champion plug application book and it listed the J8C as the correct plug. Apparently the J4J is discontinued. I picked up a set of the J8C plugs and installed them and the motor runs great in the test barrel but I haven't had it on the water yet.
Just wondering if anyone can give me more info on the question of this being the correct plug or any ideas on what might be a better plug for this motor.

Hi
Those plugs will be way too hot for this motor...I have the same motor in a 69 Johnson version.
I know all the plug site list this plug but the OMC listing for this motor is for a J4C with an optional listing for a hotter J6C. Do not use resistor plugs.

Basically as explained to me by an OMC cert mechanic...if you do alot of wide open throttle running then use the J4C and if u are slow running as in trolling quite a bit then use the hotter J6C. I think the plugs you got would be too hot and may cause damage with alot of wide open throttle running.

I use the J4C and they run perfect brown color with alot of mixed running speeds...found the plugs for cheap at autozone.

The J4C is a great plug for your engine. Buy them and enjoy!

Thanks guys, I was a little worried that the hotter plug might not be the right move, I did pick up a pair of J4C's while I was there and was going to try both plugs but the thing ran so good in the test barrel with the J8C's that I thought I should ask about them. I'll put in the colder plugs and put her in the water then report back.