K3 6khz filter question

[KC9EE]

I thought I read where the 6khz filter needs to be installed during assembly. I'm considering a used K3 that only has a 2.8 and a 450 now. Can the 6khz be added without too much difficulty or is this a deal breaker?

Gary
KC9EE

[John_N1JM]

It can be installed at any time.

John N1JM