Spark Plugs

[CKoenen@domain.elided (Chuck Koenen SR.)]

Greetings digesters,
A question on spark plugs. My son bought new plugs at Auto Zone for hie
1977 Scout ll with a 345 engine. The ones they gave him are Autolite
303's. When we started to change the plugs the ones in the motor now are
Autolite 86's. The existing ones (86)center electrode sticks out about
an 1/8 inch further than the new ones (303). I'm not sure why I think it
but it seems like we would be better to stick with the electrode that
extends futher into the combustion chamber. Is it worth the trip back to
town (only 12 miles) to see if we can get new #86 plugs?.
Thanks in advance
Chuck Koenen
(too lazy to create a sig file)