[Hallicrafters] SX-28A questions and parts request

[Waldo Magnuson]

Hi,
    A friend picked up a SX-28A for me recently ($75) and I'm about  
ready to work on it.  First I have a couple of questions regarding the  
unit:

1) V1 (6AB7) has been replaced with a 6BC5 using a plug-in adapter.   
My question is this a pin-to-pin replacement?  I suspect the 6BC5 is a  
lower noise replacement.  True?

2)  Underneath between V7 (6B8 - 2nd Det.) and V11 (6J5 - Beat Osc.) a  
tube (6AL5) has been wired in.  Could this be a product detector?   
Probably remove it?

AND,

    The speaker terminals and the antenna terminals together with the  
bakelite strips have been replaced with red and black banana  
terminals.  I'd like to restore to the 500/5000 and Ant. bakelite  
strips and proper terminals.  Anyone have these parts which I could  
purchase?

    Thanks.

73,  Skip  W7WGM