1976 Dt250 my front turn signals are rusty inside bulbs stuck 1 broke off lens screw in each one. Does anyone know if the K&S 25-4155 turn signals will screw into my stock mounts. Or what are the best aftermarket ones I can use Thanks Ron

When I've done signals in the past, I've found that aftermarket is... well... aftermarket.  Really is a crapshoot.  I'd pick a style you like and roll the dice.

I did put a set of Harley teardrop (rocket?) style lights on a Suzuki TS185 once and replaced the bulbs to the 6v version.  actually looked pretty cool, and the short arms kept them from hanging on things and breaking off.

You might want to soak the turn signals in Evaporust. This stuff is amazing and is non toxic and reusable. I buy it on Amazon.

 

I got lucky and found a nos set of turn signals that did not break the bank