How to wire two 8ohm speakers in a cab with 2 16ohm speakers

[color_tones]

Hey guys!
I have a two rock 2x12 cab with 2 16ohm 2rock 65's. Im planning on putting 2 8ohm celestions in the cab to use it with a fender blackface bassman. How would I do this as far as wiring etc...? any help would be appreciated. thanks
shawn

[phsyconoodler]

wire the speakers parallel for a 4 ohm load.
negative to negative & positive to positive.It will match the bassman head.

[tmac]

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