Weird turn signal issue
 

When I got my 911, it was in boxes, so I've never had it all together and working.
I've made a lot of progress, but I'm coming across issues that I just can't figure out...like this one -
It looks like I have 2 different front turn signal housings (one alot newer than the other) One works great - the other, not so great.
The problem is the double filament turn signal bulb - it's supposed to glow normally when the lights are on and flash bright with the turn signal on - this is how the left works.
When I install the bulb in the right housing, it immediately burns bright...and the turn signal indicator does not flash when activated.
I traced the wiring and it all seems correct to the housing.
Thanks in advance for any help.
Rob