The new sensor will be a tight fit to get back in anyway.given the age of the backplates you will probably need to clean the sensor bore hole out and again the top mounting area where it has to sit flush for depth. a light dose of rubber grease or similar to aid fitting can help,as you dont want to be hammering in !! some members have trimmed the sensors up to allow fitting but i think its best to clean the bore if possible. some use emery cloth around a drill shank etc or even a round file etc etc. just lube up the bore lightly and extra at the top end of the sensor to keep out moisture. a good clean before to remove any swarf from fettling iron filings , and a magnet may help find loose specs in crevices. im sure once you get in there you will be thinking ... i wish i had ordered a new backplate ...but thats another story, ...
