[Hallicrafters] SR-150 loading coil

[Frank F.]

Hi gentlemen,
     I'm going to finish working on my SR-150, and the only thing wrong 
with it was that the 80 meter portion of the loading coil (Illumitronic 
Engineering 051-003348) had overheated, melted the plastic,  and shorted 
out about a year ago. Subsequently I was still able to use it on all the 
other bands just fine. I know these are virtually unavailable now. My 
quick question is about the 80 meter portion of the coil only. I have 
removed the old plastic and am planning to use strips of brown circuit 
board material to reform the last 6 turns (the 80 meter portion).
The last 6 turns at 1 1/4" diameter and spaced very closely at 16 tpi 
appears to be around 1.5 uH.
It's a bit tricky to get the wire so close as to get 16 tpi (while 
gluing, etc.)  but it's doable if absolutely necessary. If I were to use 
12 tpi it would put the coil at 1.2 uH and probably the center frequency 
about 1MHz off (up 1 MHz).
My question is, does anyone know of the ballpark figure (taking the coil 
Q into consideration) of the frequency range that the unit was able to 
tune originally, just 3.5-4 MHz or quite a bit wider?
Also, if I were to use 12 tpi instead of 16 and the above consideration 
would not allow adequate bandwidth, could I perhaps safely alter the 
C128-129 (780  uuF pair) capacitors accordingly (to a slightly larger 
value) as to get a new "center " tuning range with the slightly modified 
coil?
Thanks for any replies, much appreciated.
73, Frank F.  K4AVL