Premier b-160 & b-220

[retrorod]

Hello, Looking for some info on the repair of a Premier B-220 Bass amp 15" combo. A harp player acquaintance brought over his working B-160 and his non-working,newly purchased B-220. The B-220 was damaged in shipment(magnet sheared loose and took out a homeade EF86 sustitute). At some point a 'creative' repairman fashioned a 9pin to 7pin convertor that held a 6AU6 tube and was inserted in the EF86 socket. This was demolished in the loose magnet incident. Is that even a compatible tube subsitute? I have seen no such substitute for the EF86(6267). I know they cost like $50 vs $5 for the 6AU6. Further, the B220 is fitted with 6V6 power tubes and what appears to be factory SS rectification.
The functioning B-160 has the original EF86, has 7591A power tubes, and a 5U4G rectifier vs the 5Y3 that the chassis is labeled. This amp sounds wonderfull with guitar, although the harp player would like a little more power from it!?!
Seems like the chassis/circuit are almost identical in these two amps. I am just getting into it, however.
I figure I can borrow the EF86 form the B160 to do further testing.
Can anyone shed some more light on these old Premiers? I have the B-160 schem. but can,t find much more than that. Should I snag an EF86 or are there any other substitute mods that could be persued? Thanks!
I can follow up with more info as I get my hands dirty...Rod

[retrorod]

Hey, I have moved this post over to MAINTENANCE,TROUBLESHOOTING AND REPAIR Thanks!