[Test-Equipment] Question about Wavetek 105 Function Generator

[Barry]

Anyone familiar with the Wavetek 105 function generator?   I recently became 
the proud owner of one and have two questions concerning the 30V amplifier 
board.

1.  There are two transistors (Q601 and Q602) on the input side of the board 
that are designated on the schematic to be a 2N2959; however, on my board, 
these both have been replaced with a 2N2102.  I've looked at the specs and 
these transistors don't really appear to be all that compatible but not sure 
about that.  Can someone comment on whether a 2N2102 is an acceptable sub in 
this application?

2.  Someone has added a resistive network that eventually goes to the base 
of Q602.  The network consists of a 27k from the +23V line to a 20k trimpot 
to another 27k that ties to the -23V line.  The wiper of the trimpot is 
connected through a 100k to the base of Q602.  The trimpot was mounted to 
the rear of the chassis with a hand-written marking that reads: OUTPUT ZERO. 
>From the text in the manual, if Q601 and Q602 are replaced, zeroing the 
output should be done by selecting an appropriate value for R602.  I'm 
wondering if instead of attempting to find a good value for R602, someone 
came up with a clever way of re-biasing one of the transistors to get the 
output to zero.  I'm wondering if I should try to find some original types 
for Q601 and Q602, and attempt to find a good value for R602, or whether 
this mod is necessary to overcome some other deficiency.  I'll have to check 
thee output to see if it's zeroing properly and I realize that if it's 
working it might be best not to mess with it, but I kind of hate to see 
hacked mods like this to original equipment.  Any comments?

Thanks,
Barry - N4BUQ