Hi, I have a question. I ordered new spark plugs for my IO-360-C, and size of thread for connect ignition lead is different. Thread to cylinder head is same, part number is same (well at least, old is Champion, new is Tempest – REM38E vs UREM38E). What I did wrong? some recomended me URE40E, instead of 38, should I reorder spark plugs? I am afraid, that those 40E will have same smaller...