transformer manufacture codes???

[simsamp]

can anyone tell me what kind of transformers these are???
Power transformer:PT-2756XP,40-16932,166-1513
these are 3 seperate sets of numbers printed on the power transformer.
there are 3 similar sets on the output tranny...
ot-100W,40-16852,and 166-0517

these are in a T.R. cust.rev.sig. v.1,100 watt;
i'm wondering where they came from,and if upgrading to mercury magnetics ,or even some old twin transformers would be worthwhile...
i spent about 12 hours de-gooping the board,and i'm slowly going through and trying to see how close it is to some of schematics i've seen...
anybody have any ideas????
thanks...