Blues Junior spkr out to Acme Low B-2...safe?

So I've been really happy with my live setup as of late:
Ashdown ABM 500 EVO II
(2) Acme Low B-2 (2x10s)

Great vintagey vibe with plenty of low-end from the cabs and decent portability. Recently though, I've been enjoying the rich tubey sounds I get with my Fender Blues Junior at bedroom practice levels. I just tried plugging its speaker out from the amp (bypassing the combo's 12" spkr) straight to one of my Acme Low B-2s. It sounded good, of course with a good amount of low end roll-off, but still desirable. (ABing of the Ashdown and Fender to come later) Yet I do have a couple of questions:

1. What can I expect from running a bass into an all-tube guitar amp to a bass cab longterm? Will the amp be able to handle the input?

2. Also, can I set an all-tube guitar amp on top of a boomy bass cab without damaging the innards of the amp?

3. Opinions. Everyone's favorite. What do you think of the prospect of gigging with a Blues Junior (amp) into two 2x10 bass cabs? Ridiculous or ridiculously awesome?

 

Thanks for the input. I cranked it up a little louder this morning and liked the overall vibe. It basically sounds similar to when I plug into the Blues Junior for practice, but without the fear of pushing the speaker too much on the low end. Could be good for an all-tube tone at coffee-shop style venues? I'd really like to get an all-tube bass combo or head, but unfortunately the price point is a big barrier. At least now I have an alternative to my hybrid Ashdown.

I've actually been thinking of unloading my Blues Junior (as I don't play g****r much) along with a few pedals to fund a bass tube combo. Are there any decent all-tube combos to be had in the $500 range?

 

Both cabs have an 8ohm impedance. I think I read somewhere that BJ combos run at 8ohms, but are fine running at 4 (if I were to hook the other cab up in parallel).

 

And I would think that the amp would be ok running at 4ohms, as there is an extra speaker out in addition to the one going to its 12" speaker @8ohms, so it would make sense that it could run below 8ohms, since taking advantage of the speaker out in addition to the one in the combo would sum up to an impedance less than 8 anyway, right?

 

Ah, well that clears things up. One 2x10 cab should be enough anyway.